FiiO have designed the CP13 with large oval buttons for playback controls (play, stop, rewind, fast-forward) on one side, while down the other side you will find a sleek volume dial, a USB-C port for charging, a 3.5mm headphone input and a status LED. CP13 incorporates the imported audiophile op-amp JRC5532, a classic reproduction known as the "king of op-amps." Coupled with the all-analogue circuit processing, it delivers familiar melodies with a lingering and nuanced sound. Crafted meticulously with full aluminium alloy, CP13's dual-tone casing showcases a seamless blend of form and function, with a "zero" visible screws design, enhancing both texture and aesthetics. Additionally, the buttons use a tough oxidation process, ensuring durability and corrosion resistance. The aluminium alloy volume knob features a large-sized analogue volume potentiometer, offering better stability, reliability, and an improved adjustment feel compared to regular cassette players using flatter potentiometers. CP13 features a high-capacity 1800mAh lithium battery, providing more power and longer lifespan, offering over 13 hours of continuous playback and an outstanding standby time of over 268 days. CP13 is equipped with a dual-mode power supply design, supporting both battery and Type-C charging. Connecting to a 5V power adapter enables charging, with mature charging, power supply, and overvoltage protection circuits for added peace of mind. FiiO have designed the CP13 with large oval buttons for playback controls (play, stop, rewind, fast-forward) on one side, while down the other side you will find a sleek volume dial, a USB-C port for charging, a 3.5mm headphone input and a status LED.