Microsoft Wired Desktop 400. Device interface: USB, Keyboard layout: QWERTY. Keyboard dimensions (WxDxH): 456 x 160 x 25 mm, Mouse dimensions (WxDxH): 57.9 x 113.4 x 38 mm. Minimum hard disk space: 60 MB. Battery technology: Alkaline, Battery type: AA. Operating temperature range (T-T): 0 - 40 °C, Storage temperature range (T-T): -40 - 60 °C