Thank you for viewing. I've decided to sell this keyboard because I've switched to using a different one. I used it almost every day for work for about a year after purchasing it, so frequently used keys like Enter, Backspace, and Space, as well as some alphabet keys, show wear and tear and have a shine. Please refer to the photos for details. However, there are no particular functional issues, such as keys not responding well, and it can still be used as a keyboard. This is a used item, including the period of use, so please refrain from purchasing if you are concerned. I will also send the remaining battery power, although it's only a small amount. The sale includes only the keyboard itself and the Unifying USB receiver; the manual and box are not included. Returns are generally not accepted. Thank you for your understanding. Please feel free to comment if you have any questions. Thank you. From the official website: The "K580" is a full-size keyboard with a number pad, featuring a compact and modern design. It supports up to two devices, allowing you to easily switch between devices such as smartphones, tablets, and computers with a single switch. It also features low-profile, quiet keys, providing a quiet work environment to enhance concentration and a comfortable typing experience suitable for long hours of use.