Thank you for viewing. This is the FiiO BTR13 wireless portable headphone amplifier. It has been used, but there are no major scratches or stains. It's a practical item as it doesn't have the original box. It works without any problems. Its functions include making wired headphones wireless, and also enhancing the sound quality of wired connections. Although it's not an expensive product, it's very compact and a great option for those who want to enjoy high-quality sound on the go. I connected wired headphones to my iPhone via Bluetooth, and the sound quality improved significantly even with the iPhone's AAC connection. Of course, high-resolution audio is also supported. Furthermore, by switching modes, it also functions as a DAC for wired connections. In this case, you connect an audio cable (3.5mm, 4.4mm compatible) from your headphones to the BTR13, and then connect a USB cable from the BTR13 to your smartphone or PC. It's very convenient and allows for a definite improvement in sound quality and volume. To get you started right away, I'm also including relatively high-quality audio cables (3.5mm) and an audio USB cable. There is no original box. Only the main unit and two cables are included. Thank you for your consideration.