Thank you for viewing. This is an HHKB PD-KB400W for sale. I haven't used it for about a year because I bought a new one. The left Alt key sometimes didn't return properly after being pressed, taking a few seconds to go back to normal. I contacted support at the time, but they said it wasn't covered by the warranty (as shown in the attached image). When listing it, I cleaned the keycaps and the main body and checked its operation for about an hour, but the problem with the left Alt key didn't occur for some reason. Since it's unknown if the issue will occur during prolonged use, it's being sold as a "defective item." Due to the above circumstances, I recommend this for those who can repair it themselves or those who don't use the left Alt key very often (you can swap Fn and Alt using the DIP switch). A Bird Electron silent mat is attached to the bottom. I lost the original cable, so I'm including a replacement third-party cable. I'm not considering any price reductions, so please understand. ----- This is an HHKB Professional 2 with silent mechanical switches, a white/gray keyboard with an English layout. - Model Name: HHKB Professional 2 - Color: White/Gray - Key Layout: English - Switch Type: Silent Mechanical Switch - Included Items: Instruction manual Thank you for viewing. Connection type... Wired Key switch... Capacitive non-contact method Keyboard layout... English