The Basecamp Thermolite synthetic sleeping bag is for those who prefer a luxurious and versatile sleep system. Each side of the Basecamp has a full-length side zipper; a third zipper can be found in the foot box zipper. The result is unmatched ventilation and the ability to remove the entire top section to use as a quilt. WaveLoft construction allows the Thermolite insulation to expand out into air-trapping curves for maximum warmth, and the overall shape of the Basecamp allows you to sleep in any position you choose.
The Basecamp Thermolite synthetic sleeping bag is for those who prefer a luxurious and versatile sleep system. Each side of the Basecamp has a full-length side zipper; a third zipper can be found in the foot box zipper. The result is unmatched ventilation and the ability to remove the entire top section to use as a quilt. WaveLoft construction allows the Thermolite insulation to expand out into air-trapping curves for maximum warmth, and the overall shape of the Basecamp allows you to sleep in any position you choose.
The Basecamp Thermolite synthetic sleeping bag is for those who prefer a luxurious and versatile sleep system. Each side of the Basecamp has a full-length side zipper; a third zipper can be found in the foot box zipper. The result is unmatched ventilation and the ability to remove the entire top section to use as a quilt. WaveLoft construction allows the Thermolite insulation to expand out into air-trapping curves for maximum warmth, and the overall shape of the Basecamp allows you to sleep in any position you choose.
The Basecamp Thermolite synthetic sleeping bag is for those who prefer a luxurious and versatile sleep system. Each side of the Basecamp has a full-length side zipper; a third zipper can be found in the foot box zipper. The result is unmatched ventilation and the ability to remove the entire top section to use as a quilt. WaveLoft construction allows the Thermolite insulation to expand out into air-trapping curves for maximum warmth, and the overall shape of the Basecamp allows you to sleep in any position you choose.
Last updated at 05/03/2026 01:50:40
Basecamp Bc3 Sleeping Bag (-5 °C)
Free 60-day returns
Sea To Summit Basecamp Bc III Synthetic Sleeping Bag - Regular
Free delivery between Tue – Wed
originally posted on seatosummitusa.com
6’1 210lbs. For me, it’s Extremely Comfortable and roomy. I’m a Wildland Firefighter, so it will be getting put to good use. I like that youCan unzip at your feet for ventilation. It won’t always be cold out. Most of the summer it’s still pretty warm at night in California. I like those features that allow you to make adjustments for the temperature.
originally posted on seatosummitusa.com
I bought this product after thorough research of the options. Examining offerings from Big Agnes, Exped, Nemo and others, I landed on the Basecamp for it's universal compatibility with sleeping pads, an excellent price point, and design that included a well designed, mummy bag style hoods that can be cinched to a pinhole. or opened up for warmer eveningsThis 2 person sleeping bag surpassed all expectations as a comfortable 3-season 2 person option. It is cost-effective, light and warm for a synthetic bag. It works well for both car camping and backpacking though, being a 2 person bag it is obviously on the on the bulky side. This was tested with the Exped Synmat Duo though it includes pad straps making it nearly universally compatible. I recommend this bag ... MoreI bought this product after thorough research of the options. Examining offerings from Big Agnes, Exped, Nemo and others, I landed on the Basecamp for it's universal compatibility with sleeping pads, an excellent price point, and design that included a well designed, mummy bag style hoods that can be cinched to a pinhole. or opened up for warmer eveningsThis 2 person sleeping bag surpassed all expectations as a comfortable 3-season 2 person option. It is cost-effective, light and warm for a synthetic bag. It works well for both car camping and backpacking though, being a 2 person bag it is obviously on the on the bulky side. This was tested with the Exped Synmat Duo though it includes pad straps making it nearly universally compatible. I recommend this bag frequently to couples interested in sleeping together on their outdoor pursuits but would like a bag more suited to lightweight and technical adventures than the classic 2 person bag: 2 rectangular bags zipped together.
originally posted on seatosummitusa.com
After 40 years of buying at least 20 different sleeping bags I've finally found the one. This has several great features that I really haven't found elsewhere. It packs up surprisingly small for a "basecamp" bag, smaller than my previous backpacking bags excepting a 50° i use during warm weather. Secondly this has plenty of shoulder girth, which is rare. I can get both arms in comfortably, I have a 48" chest. and have had a hard time finding a bag that fits me well. Lastly it's good for anything from 50-20°. I bought the 10° bag and it might be a bit cold at that temperature, but at 20° it does great. With two side zippers and a foot zipper you can make it work in warm temps too, or use it as a comforter. Lastly it's a got a functional hood you'll actually use. A 5 ... MoreAfter 40 years of buying at least 20 different sleeping bags I've finally found the one. This has several great features that I really haven't found elsewhere. It packs up surprisingly small for a "basecamp" bag, smaller than my previous backpacking bags excepting a 50° i use during warm weather. Secondly this has plenty of shoulder girth, which is rare. I can get both arms in comfortably, I have a 48" chest. and have had a hard time finding a bag that fits me well. Lastly it's good for anything from 50-20°. I bought the 10° bag and it might be a bit cold at that temperature, but at 20° it does great. With two side zippers and a foot zipper you can make it work in warm temps too, or use it as a comforter. Lastly it's a got a functional hood you'll actually use. A 5 * bag.
| Lower Limit | −12 °C |
| Shape | Contoured Rectangular |
| Max. User Height | 183 cm |
| Internal Girth | 194 cm Chest | 190 cm Hip | 142 cm Foot |
| External Dimensions | 215L x 97W cm |
Basecamp Bc3 Sleeping Bag (-5 °C)
Free 60-day returns
Sea To Summit Basecamp Bc III Synthetic Sleeping Bag - Regular
Free delivery between Tue – Wed
6’1 210lbs. For me, it’s Extremely Comfortable and roomy. I’m a Wildland Firefighter, so it will be getting put to good use. I like that youCan unzip at your feet for ventilation. It won’t always be cold out. Most of the summer it’s still pretty warm at night in California. I like those features that allow you to make adjustments for the temperature.
I bought this product after thorough research of the options. Examining offerings from Big Agnes, Exped, Nemo and others, I landed on the Basecamp for it's universal compatibility with sleeping pads, an excellent price point, and design that included a well designed, mummy bag style hoods that can be cinched to a pinhole. or opened up for warmer eveningsThis 2 person sleeping bag surpassed all expectations as a comfortable 3-season 2 person option. It is cost-effective, light and warm for a synthetic bag. It works well for both car camping and backpacking though, being a 2 person bag it is obviously on the on the bulky side. This was tested with the Exped Synmat Duo though it includes pad straps making it nearly universally compatible. I recommend this bag ... MoreI bought this product after thorough research of the options. Examining offerings from Big Agnes, Exped, Nemo and others, I landed on the Basecamp for it's universal compatibility with sleeping pads, an excellent price point, and design that included a well designed, mummy bag style hoods that can be cinched to a pinhole. or opened up for warmer eveningsThis 2 person sleeping bag surpassed all expectations as a comfortable 3-season 2 person option. It is cost-effective, light and warm for a synthetic bag. It works well for both car camping and backpacking though, being a 2 person bag it is obviously on the on the bulky side. This was tested with the Exped Synmat Duo though it includes pad straps making it nearly universally compatible. I recommend this bag frequently to couples interested in sleeping together on their outdoor pursuits but would like a bag more suited to lightweight and technical adventures than the classic 2 person bag: 2 rectangular bags zipped together.
After 40 years of buying at least 20 different sleeping bags I've finally found the one. This has several great features that I really haven't found elsewhere. It packs up surprisingly small for a "basecamp" bag, smaller than my previous backpacking bags excepting a 50° i use during warm weather. Secondly this has plenty of shoulder girth, which is rare. I can get both arms in comfortably, I have a 48" chest. and have had a hard time finding a bag that fits me well. Lastly it's good for anything from 50-20°. I bought the 10° bag and it might be a bit cold at that temperature, but at 20° it does great. With two side zippers and a foot zipper you can make it work in warm temps too, or use it as a comforter. Lastly it's a got a functional hood you'll actually use. A 5 ... MoreAfter 40 years of buying at least 20 different sleeping bags I've finally found the one. This has several great features that I really haven't found elsewhere. It packs up surprisingly small for a "basecamp" bag, smaller than my previous backpacking bags excepting a 50° i use during warm weather. Secondly this has plenty of shoulder girth, which is rare. I can get both arms in comfortably, I have a 48" chest. and have had a hard time finding a bag that fits me well. Lastly it's good for anything from 50-20°. I bought the 10° bag and it might be a bit cold at that temperature, but at 20° it does great. With two side zippers and a foot zipper you can make it work in warm temps too, or use it as a comforter. Lastly it's a got a functional hood you'll actually use. A 5 * bag.
I love everything about this bag except it is not as warm as the rating would suggest. Long story, short, I'm at 5'11 190lb male, and I will be treating this bag as comfortable down to 40 degrees, not the 20 degrees that was advertised.I took it camping when the temperature was supposed to get below freezing, maybe 28 degrees. I had long underwear on, wool socks, and a beanie, and I was in a tent with the rain fly on and two of my kids (so all that generated and retained some heat...maybe a few degrees). Anyways, there was no way I was staying warm enough in this bag. I'm confident I would have survived, but there would have been no sleeping. Luckily, I brought my Rumpl blanket just in case, so I threw that over me and was fine after that. I also have a 20 degree ... MoreI love everything about this bag except it is not as warm as the rating would suggest. Long story, short, I'm at 5'11 190lb male, and I will be treating this bag as comfortable down to 40 degrees, not the 20 degrees that was advertised.I took it camping when the temperature was supposed to get below freezing, maybe 28 degrees. I had long underwear on, wool socks, and a beanie, and I was in a tent with the rain fly on and two of my kids (so all that generated and retained some heat...maybe a few degrees). Anyways, there was no way I was staying warm enough in this bag. I'm confident I would have survived, but there would have been no sleeping. Luckily, I brought my Rumpl blanket just in case, so I threw that over me and was fine after that. I also have a 20 degree synthetic bag from REI, and you can tell it is just a more substantial bag. I gave that to my friend for that trip (he slept in a tent with his kids) and he was fine. Not sure if the difference is just the size/width or the level of the insulation. This is a bigger, wider bag than my REI bag, so it's clearly going to take more body heat to keep it warm.But I love everything else about the bag, and I am going to keep it. I like the quality of the material, the packed size, and the roominess. I sleep on my side with my arms bent up and hands near or under my pillow. Most mummy bags constrain this. Also, I like to have a little room for my legs to move around. So, I love this bag. It's just not as warm as advertised.
The pros. This is a great bag for side sleepers...in warm weather. I bought it knowing that I need a warmer rated mummy bag for cold temps, but (con) I was honestly very surprised at how cold this bag was. For a summer bag for kayaking or camping above 60 degrees, it's fine alone. I purposely tested it over a weekend, knowing we'd have temps down into the low 40s. I also took a wool blanket and fleece sheet to use INSIDE the bag for warmth and even in a thermal sleep set, two fleece jackets, hat, gloves and socks, I could barely sleep. The cold just seeps in everywhere and I actually pulled a heavier fleece jacket on over the outside of the bottom of the bag to keep my legs warmer. Of my four bags, this is probably the worse as far as temperature ratings go, but for ... MoreThe pros. This is a great bag for side sleepers...in warm weather. I bought it knowing that I need a warmer rated mummy bag for cold temps, but (con) I was honestly very surprised at how cold this bag was. For a summer bag for kayaking or camping above 60 degrees, it's fine alone. I purposely tested it over a weekend, knowing we'd have temps down into the low 40s. I also took a wool blanket and fleece sheet to use INSIDE the bag for warmth and even in a thermal sleep set, two fleece jackets, hat, gloves and socks, I could barely sleep. The cold just seeps in everywhere and I actually pulled a heavier fleece jacket on over the outside of the bottom of the bag to keep my legs warmer. Of my four bags, this is probably the worse as far as temperature ratings go, but for a summer bag for kayaking trips, it's great. But it is not worth the price listed unless, like me, you can get yours for a superior sales price.
I'm a 5'4", 245-250 lb (3x-4x) woman. Most sleeping bag/mummy bag options out there don't work for my body type. I also tend to move around a lot as I sleep, so I was so happy to find Sea to Summit has these "roomy" options. I got the regular size, 10 degree bag and it was a great fit. Please make sure to advertise these bags to the plus size community because we're looking for these options!I tend to sleep on the warm side, with the exception of my feet, so I was excited to test out how this bag would hold up when I found out that the first evening of a planned camping trip would get down to 30-35 degrees.For reference, my sleeping pad was a Klymit Insulated Static V Luxe with a yoga mat underneath it and a camping blanket nearby in case I needed more warmth ... MoreI'm a 5'4", 245-250 lb (3x-4x) woman. Most sleeping bag/mummy bag options out there don't work for my body type. I also tend to move around a lot as I sleep, so I was so happy to find Sea to Summit has these "roomy" options. I got the regular size, 10 degree bag and it was a great fit. Please make sure to advertise these bags to the plus size community because we're looking for these options!I tend to sleep on the warm side, with the exception of my feet, so I was excited to test out how this bag would hold up when I found out that the first evening of a planned camping trip would get down to 30-35 degrees.For reference, my sleeping pad was a Klymit Insulated Static V Luxe with a yoga mat underneath it and a camping blanket nearby in case I needed more warmth (since everything was new and this was my first camping trip in a long while.) Pillow was a Sea to Summit regular size Foam Core pillow. Hopped in the bag that evening with my base layer on, some wool socks, liner gloves, and a beanie. Got an amazing night's sleep! Didn't need the blanket. My feet were a little chilly in the morning, but that was because I forgot I could attach myself to the pad and managed to wiggle down it while sleeping to where my feet weren't on the pad anymore. The bag is so soft and comfortable too. I cannot wait for my next camping trip!
I bought the long version - to compliment the regular I already have. I'm in between size length so now, I can bring someone with me and I'll always have sleeping bag to fit them.I'm 5'10 and I do feel like I'm swimming in the long. I sleep hot and love cold spots so the extra space works great for me.I'm a 2x-3x and this bag could comfortably fit 4x, possibly 5x or 6x.Great for those who want something roomy, but isn't a sleep system as I love that the Basecamp has a little insulation on the backside, not just a quilted top.True to size, but feels like it runs big, only because its the BIGGEST and WIDEST I've ever slept in.
I'm 5'9" and a somewhat cold sleeper. To that end, I know that I need a bag with a strong temperature rating. I was looking for a bag for spring/summer/early fall kayak camping when temps are not less than 40-50 degrees, and this will suit me fine. However, I slept on an insulated pad in temps no lower than 50 degrees with a pair of synthetic thermals on and while I never got cold, you could feel the chill through the top of the bag. Therefore, there is no way I would trust this in lower temperatures for my own comfort. (This isn't an unusual problem in bag designs from most manufacturers, but I wish the industry would do better.) Having said that, the biggest pro is the expansive shape for a side sleeper. Cons: the weird, stiff materials used around the zippers and ... MoreI'm 5'9" and a somewhat cold sleeper. To that end, I know that I need a bag with a strong temperature rating. I was looking for a bag for spring/summer/early fall kayak camping when temps are not less than 40-50 degrees, and this will suit me fine. However, I slept on an insulated pad in temps no lower than 50 degrees with a pair of synthetic thermals on and while I never got cold, you could feel the chill through the top of the bag. Therefore, there is no way I would trust this in lower temperatures for my own comfort. (This isn't an unusual problem in bag designs from most manufacturers, but I wish the industry would do better.) Having said that, the biggest pro is the expansive shape for a side sleeper. Cons: the weird, stiff materials used around the zippers and the measly straps. This is advertised as luxurious bag and the pad straps were a real part in my decision, except that they barely fit around a 25x33" pad and the straps never remain snapped. Why design a larger bag, but not allow that people who might want or need this kind of design would also then appreciate or use a larger sleeping pad? Go figure. I got mine for a very good price, because while I like it, I don't feel it's a $200 sleeping bag.
In all my years of travel and outdoor living, this bag is the one I am most excited about and pleased to own.It's actually warmer than I need mostbof the time living in the South, but I also picked up a Coolmax liner, a silk liner, and a cotton liner. That way I can utilize the customize and modular nature of this high-tech bag to suit my needs for each trip.This is the largest item in my outdoor kit, but well worth it!
This bag is absolutely amazing! My feet are usually cold so I wasn’t sure about having such a large toe box. I was wrong… I was toasty warm in mid to low 30s, sleeping in thin pants and a t-shirt. I did a bit of cowboy camping in Paria Canyon (Utah/Arizona) with this bag paired with my Recharge XL Sleeping Pad and was super comfortable. I was amazed that there was no cold air seeping in from the zippers. Not only have they designed this bag to have the zippers overlap, they have zippers on both sides. As well, the toe box has a separate zipper in case you have a warmer night and need to air out the toes or kick out a leg. I was super impressed. It’s hard for me to sleep in tight spaces so the flexibility to sleep however I wanted and still have room to switch sides, ... MoreThis bag is absolutely amazing! My feet are usually cold so I wasn’t sure about having such a large toe box. I was wrong… I was toasty warm in mid to low 30s, sleeping in thin pants and a t-shirt. I did a bit of cowboy camping in Paria Canyon (Utah/Arizona) with this bag paired with my Recharge XL Sleeping Pad and was super comfortable. I was amazed that there was no cold air seeping in from the zippers. Not only have they designed this bag to have the zippers overlap, they have zippers on both sides. As well, the toe box has a separate zipper in case you have a warmer night and need to air out the toes or kick out a leg. I was super impressed. It’s hard for me to sleep in tight spaces so the flexibility to sleep however I wanted and still have room to switch sides, sleep on my back, or sleep on my stomach without feeling confined was great. The bag has straps so attaching it around my sleeping pad made it to where it did not move at all through the night even though I was. Overall hugely impressed!
| Lower Limit | −12 °C |
| Shape | Contoured Rectangular |
| Max. User Height | 183 cm |
| Internal Girth | 194 cm Chest | 190 cm Hip | 142 cm Foot |
| External Dimensions | 215L x 97W cm |
