FiiO K1 portable Headphone Amplifier and DAC. The thumb-sized K1 from FiiO is a portable headphone amplifier and DAC with mastering quality sound that supports resolutions of up to 24-bit/ 96 kHz. The unit offers true plug-and-play operation with no batteries to charge and no drivers required for operation. The K1 also self-mutes when powering on or off, reducing harmful transients. The all-metal chassis is sandblasted for optimal sheen, texture, durability of appearance, and hand grip. The K1 ships with a removable clip and a USB connection cable. So buy this Fiio K1 portable Headphone Amplifier and DAC - Plug and Play Now £35.99.