ER-X-SFP Quick Start Guide
ER-X-SFP Quick Start Guide
ER-X-SFP Quick Start Guide
ER-X-SFP Quick Start Guide
Last updated at 06/22/2026 07:58:47
Ubiquiti Networks EdgeRouter 5-Port Advanced Gigabit Ethernet Router with SFP
Delivery between 24–29 June $19.98
EdgeRouter-X-SFP -5 x 24V PoE
Delivery $24.17
Ubiquiti EdgeMAX EdgeRouter X Gigabit Router w/ PoE Passthrough and SFP port
Delivery between 24 June – 2 July $11.50
Ubiquiti Edgeroute ER-X-SFP Advanced Gigabit Ethernet Router, 5 Gigabit RJ45 Ports, Passive PoE Support, SFP
Delivery between Wed – Fri $12
ER-X-SFP Ubiquiti UISP EdgeRouter X SFP
Delivery $16.70
Ubiquiti EdgeRouter X - 5-Port Gigabit Router 1 SFP - 24v Passive PoE Out (Limited) - 880MHz Dual Core Processor - 256MB RAM - 1 Year RTB
Delivery $16.50
Ubiquiti EdgeRoute Advanced Gigabit Ethernet Router - Compact but powerful router sporting (5) Gigabit RJ45 ports with passive PoE support and an SFP
Delivery $15
Ubiquiti ER-X-SFP wired router Black
Delivery $25
Ubiquiti Networks EdgeRouter ER-X-SFP 6 Port PoE Gigabit Ethernet Router
Delivery between 25–29 June $16.65
Ubiquiti ER-X-SFP wired router Black
originally posted on pbtech.co.nz
Great piece of tech - allowed me to set up as a router in my Hubble cabinet (in our garage) where space was tiny and I have 19 data ports via a NetGear 24 port switch (unmanaged) in my new home. Once set up UE-X (with Contact Broadband Fibre via Ultrafast fibre modem) I was able to utilise a data point elsewhere in our new home to use their standard Contact Broadband NetComm 18 ACV router but in BRIDGE mode. I set this up in BRIDGE mode and engaged/set up all wifi modes using this router. I reckon I have saved over $500+ by NOT having to use a fancy mesh router system. I have a 260m2 2 story house and wifi is good to OK throughout the house. This setup should be standard for all new homes. Make sure you "plan" your data throughout your house. If I have a signal ... MoreGreat piece of tech - allowed me to set up as a router in my Hubble cabinet (in our garage) where space was tiny and I have 19 data ports via a NetGear 24 port switch (unmanaged) in my new home. Once set up UE-X (with Contact Broadband Fibre via Ultrafast fibre modem) I was able to utilise a data point elsewhere in our new home to use their standard Contact Broadband NetComm 18 ACV router but in BRIDGE mode. I set this up in BRIDGE mode and engaged/set up all wifi modes using this router. I reckon I have saved over $500+ by NOT having to use a fancy mesh router system. I have a 260m2 2 story house and wifi is good to OK throughout the house. This setup should be standard for all new homes. Make sure you "plan" your data throughout your house. If I have a signal issue on a particular spot, I have an old CISO WAG160N I can use in bridge mode with same 2.4 wifi SSD and Bob's your uncle. My grown up kids will be pleased when they stay!! Whanau proof Tech from me!! Economical too!
originally posted on digitec.ch
I cannot recommend this device in any kind of way at this point. As soon as there's multiple connections on it (for example internal routing) it's completely crashing down, with huge connection instabilities to all connected devices. It's maybe able to route around 100Mbit/s traffic around each device, but anything beyond that cracks it, locking down the speed and increasing latency.Bad hardware. DO NOT BUY.
originally posted on scan.co.uk
I was having a lot of issues with ping spikes. My network is quite large (40+ devices) and having done some tests with my Orbi mesh router and also the original Sky router I spotted I was suffering an issue called buffer bloat. Id never heard of this but made instant sense. Streaming Netflix, downloading, normal speed tests all showed an excellent connection, however games, zoom calls as well as my work VPN would suffer glitches. Games could be near unplayable despite 150Mbps speeds.Did some research and this ER4 has completely changed my network. It’s now so stable and with no ping issues whatsoever.My set up:1. EdgeRouter 4 is connected directly to ONT fibre connection2. Netgear orbi in bridge mode providing wifi access pointsIt does take a lot of set up ... MoreI was having a lot of issues with ping spikes. My network is quite large (40+ devices) and having done some tests with my Orbi mesh router and also the original Sky router I spotted I was suffering an issue called buffer bloat. Id never heard of this but made instant sense. Streaming Netflix, downloading, normal speed tests all showed an excellent connection, however games, zoom calls as well as my work VPN would suffer glitches. Games could be near unplayable despite 150Mbps speeds.Did some research and this ER4 has completely changed my network. It’s now so stable and with no ping issues whatsoever.My set up:1. EdgeRouter 4 is connected directly to ONT fibre connection2. Netgear orbi in bridge mode providing wifi access pointsIt does take a lot of set up and although I’m fine with technology I’m no network expert. If I can manage it though anyone could with the help of Google and YouTube.Notes1. Set up smart queue2. Sky uses MER so I had to set up DHCP Option 61. The syntax for this is hard and took some trial and error using the config tree3. IPv6 caused vpn issues. Tried disabling it but still had problems possibly at local machine. In end I found a page on Google that described the IPv6 settings you need. Problem then solvedI honestly think every home should just have one of these makes my network and internet access flawless but it takes some configuring. I’d love to see more options in UI to configure without having to go to config tree which requires some knowledge to understand.
| Dimensions | 142 x 75 x 23 mm (5.59 x 2.95 x 0.91") |
| Max. Power Consumption | 5W |
| Power Input | 24VDC, 2.5A Power Adapter (Included) |
| Power Supply | External AC/DC Adapter |
| Supported Voltage Range | 9 to 26VDC |
Ubiquiti Networks EdgeRouter 5-Port Advanced Gigabit Ethernet Router with SFP
Delivery between 24–29 June $19.98
EdgeRouter-X-SFP -5 x 24V PoE
Delivery $24.17
Ubiquiti EdgeMAX EdgeRouter X Gigabit Router w/ PoE Passthrough and SFP port
Delivery between 24 June – 2 July $11.50
Ubiquiti Edgeroute ER-X-SFP Advanced Gigabit Ethernet Router, 5 Gigabit RJ45 Ports, Passive PoE Support, SFP
Delivery between Wed – Fri $12
ER-X-SFP Ubiquiti UISP EdgeRouter X SFP
Delivery $16.70
Great piece of tech - allowed me to set up as a router in my Hubble cabinet (in our garage) where space was tiny and I have 19 data ports via a NetGear 24 port switch (unmanaged) in my new home. Once set up UE-X (with Contact Broadband Fibre via Ultrafast fibre modem) I was able to utilise a data point elsewhere in our new home to use their standard Contact Broadband NetComm 18 ACV router but in BRIDGE mode. I set this up in BRIDGE mode and engaged/set up all wifi modes using this router. I reckon I have saved over $500+ by NOT having to use a fancy mesh router system. I have a 260m2 2 story house and wifi is good to OK throughout the house. This setup should be standard for all new homes. Make sure you "plan" your data throughout your house. If I have a signal ... MoreGreat piece of tech - allowed me to set up as a router in my Hubble cabinet (in our garage) where space was tiny and I have 19 data ports via a NetGear 24 port switch (unmanaged) in my new home. Once set up UE-X (with Contact Broadband Fibre via Ultrafast fibre modem) I was able to utilise a data point elsewhere in our new home to use their standard Contact Broadband NetComm 18 ACV router but in BRIDGE mode. I set this up in BRIDGE mode and engaged/set up all wifi modes using this router. I reckon I have saved over $500+ by NOT having to use a fancy mesh router system. I have a 260m2 2 story house and wifi is good to OK throughout the house. This setup should be standard for all new homes. Make sure you "plan" your data throughout your house. If I have a signal issue on a particular spot, I have an old CISO WAG160N I can use in bridge mode with same 2.4 wifi SSD and Bob's your uncle. My grown up kids will be pleased when they stay!! Whanau proof Tech from me!! Economical too!
I cannot recommend this device in any kind of way at this point. As soon as there's multiple connections on it (for example internal routing) it's completely crashing down, with huge connection instabilities to all connected devices. It's maybe able to route around 100Mbit/s traffic around each device, but anything beyond that cracks it, locking down the speed and increasing latency.Bad hardware. DO NOT BUY.
I was having a lot of issues with ping spikes. My network is quite large (40+ devices) and having done some tests with my Orbi mesh router and also the original Sky router I spotted I was suffering an issue called buffer bloat. Id never heard of this but made instant sense. Streaming Netflix, downloading, normal speed tests all showed an excellent connection, however games, zoom calls as well as my work VPN would suffer glitches. Games could be near unplayable despite 150Mbps speeds.Did some research and this ER4 has completely changed my network. It’s now so stable and with no ping issues whatsoever.My set up:1. EdgeRouter 4 is connected directly to ONT fibre connection2. Netgear orbi in bridge mode providing wifi access pointsIt does take a lot of set up ... MoreI was having a lot of issues with ping spikes. My network is quite large (40+ devices) and having done some tests with my Orbi mesh router and also the original Sky router I spotted I was suffering an issue called buffer bloat. Id never heard of this but made instant sense. Streaming Netflix, downloading, normal speed tests all showed an excellent connection, however games, zoom calls as well as my work VPN would suffer glitches. Games could be near unplayable despite 150Mbps speeds.Did some research and this ER4 has completely changed my network. It’s now so stable and with no ping issues whatsoever.My set up:1. EdgeRouter 4 is connected directly to ONT fibre connection2. Netgear orbi in bridge mode providing wifi access pointsIt does take a lot of set up and although I’m fine with technology I’m no network expert. If I can manage it though anyone could with the help of Google and YouTube.Notes1. Set up smart queue2. Sky uses MER so I had to set up DHCP Option 61. The syntax for this is hard and took some trial and error using the config tree3. IPv6 caused vpn issues. Tried disabling it but still had problems possibly at local machine. In end I found a page on Google that described the IPv6 settings you need. Problem then solvedI honestly think every home should just have one of these makes my network and internet access flawless but it takes some configuring. I’d love to see more options in UI to configure without having to go to config tree which requires some knowledge to understand.
I purchased this ER-X to replace a circa 2006 D-Link DFL-200 wired router / firewall appliance in my house, purely for home use, not for business. I have Verizon FiOS which, over the years, has been upgraded by Verizon (at no extra cost to me) from 15Mbps to 100Mbps. At the 15Mbps and 25Mbps speeds the DFL-200 had no trouble keeping up. But after the most recent upgrade to 100Mbps, I was actually seeing only about 34Mbps. I was hopeful the ER-X would fix that issue, and I was right.I am a retired IT professional and have extensive computer and networking background. That said, I have not worked in IT PROFESSIONALLY for 7 years. At this point, I would say my skills are at the "skilled layperson" level. Since my needs were very simple, I was able to use the ER-X ... MoreI purchased this ER-X to replace a circa 2006 D-Link DFL-200 wired router / firewall appliance in my house, purely for home use, not for business. I have Verizon FiOS which, over the years, has been upgraded by Verizon (at no extra cost to me) from 15Mbps to 100Mbps. At the 15Mbps and 25Mbps speeds the DFL-200 had no trouble keeping up. But after the most recent upgrade to 100Mbps, I was actually seeing only about 34Mbps. I was hopeful the ER-X would fix that issue, and I was right.I am a retired IT professional and have extensive computer and networking background. That said, I have not worked in IT PROFESSIONALLY for 7 years. At this point, I would say my skills are at the "skilled layperson" level. Since my needs were very simple, I was able to use the ER-X "Basic Setup" Wizard to configure the device. I had to make a few changes to match my existing network, but they were minimal and easy to find in the web interface. I never needed to use the command line interface, which others have found intimidating. I will note that the DFL-200 is functionally similar, including advanced firewall and VPN capabilities, which were all supported in the web interface.After replacing the DFL-200 with the ER-X and restarting each device on the network (to get a new IP address, which the router provides), I ran a speed test. Zoom! I was getting about 105Mbps, slightly above the "rated" FiOS speed. During the speed test I monitored the ER-X performance indicators using the web interface. The device was pretty much coasting, so if Verizon boosts me to, say, 200Mbps in the future, I should be all set. I also ran the ShieldsUp test to see whether my home network had any exposure the Internet. I am pleased to report that all unsolicited inbound TCP/UDP ports were closed by default, meaning my network is effectively invisible to the outside world. Excellent results for minimal cash and technical outlay!
To use this product properly, you need a lot of patience, some technical know-how and coffee - because once youve dived into the nitty-gritty of this device, its very difficult to let go. Ive only had this device for less than a day and have been playing with it a lot. One thing immediately that struck me is that there is nothing on Web GUI to display devices that are connected. Ive had a Linksys e4200 v1 for ages and thats a standard feature on their original firmware (replaced with DD-WRT later). You can see the devices that have leased IP addresses, but you cannot see (or at least I cannot find them) the list of devices connected to the router. Via the magic of CLI (command line interface), you can do a show arp command and this will display you the list of ... MoreTo use this product properly, you need a lot of patience, some technical know-how and coffee - because once youve dived into the nitty-gritty of this device, its very difficult to let go. Ive only had this device for less than a day and have been playing with it a lot. One thing immediately that struck me is that there is nothing on Web GUI to display devices that are connected. Ive had a Linksys e4200 v1 for ages and thats a standard feature on their original firmware (replaced with DD-WRT later). You can see the devices that have leased IP addresses, but you cannot see (or at least I cannot find them) the list of devices connected to the router. Via the magic of CLI (command line interface), you can do a show arp command and this will display you the list of devices. Not the most elegant solution, but for me it works. It may not work for other people. That is so far the only con Ive found so far. On the plus side, its nice to have a Web GUI interface for this device and unlike the Unifi Controller that I have as well. You can configure each port to be its own LAN (VLAN, have not tried it yet). The dashboard on the Web GUI is nice - not as extensive as the Unified Controller - but it has enough information for me. As for its performance, too early to tell. But if you get this and you overcome the learning curve, youll not be disappointed. If you like plug and play, no, this is not for you.
This is a great router for the price. It isn't aimed at the consumer market; it assumes you have some knowledge of networking. It is based on vyatta and linux, and you can run linux commands on it.Make sure you read the quick start guide before trying to configure it, as the router does not have a dhcp server enabled in the factory default state. However it does have a dhcp client configured on eth1, so if you already have a router with a dhcp server, you can connect the ER-X eth1 interface to your existing router's LAN, and the then connect to the ip address your router gave to the ER-X, and from there you can get a working configuration by answering a few questions in the Basic Setup Wizard. This will get you a configuration that is safe to connect to the ... MoreThis is a great router for the price. It isn't aimed at the consumer market; it assumes you have some knowledge of networking. It is based on vyatta and linux, and you can run linux commands on it.Make sure you read the quick start guide before trying to configure it, as the router does not have a dhcp server enabled in the factory default state. However it does have a dhcp client configured on eth1, so if you already have a router with a dhcp server, you can connect the ER-X eth1 interface to your existing router's LAN, and the then connect to the ip address your router gave to the ER-X, and from there you can get a working configuration by answering a few questions in the Basic Setup Wizard. This will get you a configuration that is safe to connect to the internet, and it will even allow you to configure two LANs (one on eth1, the other on the remaining 3 ports in switch0, eth2-eth4). If you configure it by connecting to eth0, you must manually configure a static ip address on your device before you connect to the ER-X at 192.168.1.1 on eth0. Before connecting, verify your PC has an address like 192.168.1.5 with subnet mask 255.255.255.0 by using ipconfig /all from a CMD prompt.If you are looking for something with active development, this is not what you want. Ubiquiti is currently only making security patches at this point, so consider this a mature product. If you want frequent updates, look at something like OpenWrt.The ER-X is very flexible and capable. Internally it is a single port router with a connection to a vlan capable switch. So any port can be configured the same as any other port, with the exception of PoE in and out ports; if you are going to use that feature you will need to use the fixed ports for that function.Ubiquiti documentation is poor. The only support is their forum.https://community.ui.com/tags/edgemax/questionsOther resources:Ubiquiti EdgeMAX help articles:https://help.ui.com/hc/en-us/sections/360008075214-EdgeRouterHere's a forum thread with many ER-X support links:https://community.ui.com/questions/BuckeyeNets-link-farm/d58f154d-8dd7-48a3-aba1-5d35fb84c9d2If you want a plug and play router appliance that is easy to use but not very flexible, then this isn't what you are looking for.If you want a router with many features, like vlan support in both router and its integrated switch, support for ipsec and openvpn and with the ability to sideload wireguard, the ability to have multiple ISP connections, and even run dynamic routing protocols like ospf, this is a good choice.
My review on this does not seem to get published. Not sure why. Here it is again. I bought this ER-X to replace a WRT54GL to improve throughput. It works great. BH had great price and delivery. I still keep the WRT54GL connected to the ER-X for expansion. I am not very network savvy. I was almost able to follow the Ubiquiti instructions, but not quite. However, it did not take long to find more explicit instructions online. Especially see: EdgeRouter X instructions at Aline or Intermedia sites, with drawings. This is what worked for me to configure the ER-X with windows 10 and charter/spectrum:Connect ER-X port 0 to PC Ethernet port.Temporarily change windows network properties, IPv4 settings, as follows:192.168.1.4255.255.255.0 (fills in ... MoreMy review on this does not seem to get published. Not sure why. Here it is again. I bought this ER-X to replace a WRT54GL to improve throughput. It works great. BH had great price and delivery. I still keep the WRT54GL connected to the ER-X for expansion. I am not very network savvy. I was almost able to follow the Ubiquiti instructions, but not quite. However, it did not take long to find more explicit instructions online. Especially see: EdgeRouter X instructions at Aline or Intermedia sites, with drawings. This is what worked for me to configure the ER-X with windows 10 and charter/spectrum:Connect ER-X port 0 to PC Ethernet port.Temporarily change windows network properties, IPv4 settings, as follows:192.168.1.4255.255.255.0 (fills in automatically)192.168.1.1Login to ER-X at http://192.168.1.1User: Ubnt (default)PW: Ubnt (default)Update ER-X firmware using upload, before doing anything else. Don't skip this step.Re-login to ER-X.Change ER-X password. Don't skip this step.Default settings should be ok for everything else for now.Accept changes, which reboots the ER-X.Change windows network properties, IPv4 settings, back to what they were, as follows:Obtain automatically.Obtain automatically.Connect ER-X port 1 to PC ethernet port.Connect ER-X port 0 to Internet from modem.Check internet connection is working.If using VOIP, re-login to ER-X, using new password, and disable SIP ALG, as follows:Config tree method:Select config tree in the top right-hand corner of the main dashboard page in the web UI.Select system on the left-hand side.Select conntrack.Select modules.Select sip.Next to the word, 'disable', select the + icon.At the very bottom of the page select the preview option and then select 'Apply'.To add WRT54GL, or other router, to ER-X, as expansion ports, as follows:Connect WRT54GL LAN port to PC ethernet port.Login to WRT54GL.Disable DHCP and set default to http://192.168.1.2Reconnect ER-X port 1 to PC ethernet port.Connect WRT54GL LAN port to available ER-X LAN port.
It's not all the time that you feel as though you got more than you paid for. I bought two of these devices to create a VPN between my aunt's house and myself, they arrived to my transhipper on time and I got them a week later. I pay extra for size/weight so was happy that B&H was efficient with their packaging. The devices themselves are slightly larger than a pack of cards and feel rock solid in your hand. I was warned that these routers aren't the most newbie friendly devices and that I should expect to get my hands dirty on the CLI. However, the GUI ended up being good enough for everything that I needed to do so far. There are MANY videos on the Internet detailing how to get these up and running, how to tweak them and how to setup various VPN configurations so ... MoreIt's not all the time that you feel as though you got more than you paid for. I bought two of these devices to create a VPN between my aunt's house and myself, they arrived to my transhipper on time and I got them a week later. I pay extra for size/weight so was happy that B&H was efficient with their packaging. The devices themselves are slightly larger than a pack of cards and feel rock solid in your hand. I was warned that these routers aren't the most newbie friendly devices and that I should expect to get my hands dirty on the CLI. However, the GUI ended up being good enough for everything that I needed to do so far. There are MANY videos on the Internet detailing how to get these up and running, how to tweak them and how to setup various VPN configurations so even though they aren't plug and play, they are still very easy to set up. I've actually had a different model on my wishlist for years but never pulled the trigger because I didn't have an actual use for it. When it was time to buy, I found that B&H had it for a lower price than other places. This is a great product at a great price and I intend to purchase two more in the near future.
The 7 year old modem-router (Billion BiPac 7300N) in my wife's shared art studio was getting buggy, with daily drop-outs, failed connections, no internet all requiring power-cycling, hard resets etc. Since we weren't using the wireless access point feature of the Billion I searched for and found the Edgerouter X. The access points were aleady Ubiquity Unifi APs, so it was nice sticking with the one manufacturer. We decided to covert the Billion into modem-only in full bridge mode. The ER-X was a bit complicated to set up at the start, but once I discovered the Wizards tab, it was a snack! For some strange reason, the more advanced set-up tabs are adjacent to the 'get started' tab, with the 'wizards' tab to the far right! Anyway, setting up with the wizard was a ... MoreThe 7 year old modem-router (Billion BiPac 7300N) in my wife's shared art studio was getting buggy, with daily drop-outs, failed connections, no internet all requiring power-cycling, hard resets etc. Since we weren't using the wireless access point feature of the Billion I searched for and found the Edgerouter X. The access points were aleady Ubiquity Unifi APs, so it was nice sticking with the one manufacturer. We decided to covert the Billion into modem-only in full bridge mode. The ER-X was a bit complicated to set up at the start, but once I discovered the Wizards tab, it was a snack! For some strange reason, the more advanced set-up tabs are adjacent to the 'get started' tab, with the 'wizards' tab to the far right! Anyway, setting up with the wizard was a breeze and we were flying in no time. I used the POE injector from one of the Unifi APs to power the ER-X which then provided pass-through POE to the same AP via eth4. The modem line-in went into eth0, leaving eth1-3 for the rest of the LAN. So far the ER-X has been trouble free, serving about twenty different clients, both wired, and wireless via the Unifi APs. The features I need to look into are remote access into the router and I have done some preliminary research into this by mostly looking at Ubiquity's support forums, but I have a way to go. All in all, I find the Ubiquity ER-X a very good option for the SOHO setting where you need to bullet-proof solution with little tinkering, but also want good statistics and feedback, and more configurability than your average consumer grade router will give you. The price speaks for itself, I think!
Oh, I like this router. I like it a lot. It is tiny. It is probably a quarter of the size of the consumer router from Cisco/Linksys, prior to the Belkin acquisition of Linksys, that it replaced. It is also a managed switch so it is much more feature packed. It can handle multiple VLANs, VPN, Firewall rules, NAT rules with DMZ roles, and the list goes on.Here is the negative: It is a managed router with an interface designed for professional network engineers. I have worked in IT professionally for nearly 25 years and I am extremely grateful that Ubiquiti included the WAN+2LAN2 Wizard as part of their management software. I was reading through the software manual to set the router up and I am thinking, I see how to configure DHCP, I see how to configure internal ... MoreOh, I like this router. I like it a lot. It is tiny. It is probably a quarter of the size of the consumer router from Cisco/Linksys, prior to the Belkin acquisition of Linksys, that it replaced. It is also a managed switch so it is much more feature packed. It can handle multiple VLANs, VPN, Firewall rules, NAT rules with DMZ roles, and the list goes on.Here is the negative: It is a managed router with an interface designed for professional network engineers. I have worked in IT professionally for nearly 25 years and I am extremely grateful that Ubiquiti included the WAN+2LAN2 Wizard as part of their management software. I was reading through the software manual to set the router up and I am thinking, I see how to configure DHCP, I see how to configure internal routes, now how do I set this up to use DHCP on one of the network ports that I plug in to the cable modem and set up that route to the private network served by this routers DHCP server through NAT? It turns out the afore mentioned wizard sets up that exact configuration which can then be easily tweaked once all the parts are in place. And that wizard matters because unlike a consumer router, there is not a dedicated jack to plug in to your modem; any of the five jacks can be configured in that role or any other role.Basically, this little guy can make your network as intricate as you can conceive with five network ports. Even with the wizard it is more involved than setting up a consumer router, but a little reading of the manual for individuals not familiar with the terms being used and it should not be much more difficult. As a final note, the manual can be downloaded from the manufacturers website and if it looks overwhelming then this probably is not the product for you.
| Dimensions | 142 x 75 x 23 mm (5.59 x 2.95 x 0.91") |
| Max. Power Consumption | 5W |
| Power Input | 24VDC, 2.5A Power Adapter (Included) |
| Power Supply | External AC/DC Adapter |
| Supported Voltage Range | 9 to 26VDC |