Item Type: Wireless Vertical Mouse Material: ABS Number of Keys: 6 Keys DPI: 800, 1200, 2400, 3200 Battery: 400mAh Lithium Battery (Included) Mouse Size: Approx. 140 x 75 x 80mm / 5.5 x 3.0 x 3.1in Receiver: Approx. 6 x 19 x 14.6mm / 0.24 x 0.75 x 0.6in 1、Ergonomic Design: Wireless vertical mouse with a unique angle of 60 degrees puts your hand in a natural grip position to avoid forearm sprain and will reduce muscle tension and defend your wrist.  2、High Sensitivity: Ergonomic mouse with 6 practical design buttons, 800dpi 1200dpi 2400dpi 3200dpi adjustable mouse movement speed, optical tracking technology has higher sensitivity than standard optical mouse for accurate tracking of various surfaces.  3、4 GHz Wireless: Wireless range of 38ft through 4 GHz wireless connection, wireless receiver is plug and play for PC, laptop and other devices.  4、Silent Design: Wireless vertical mouse with button silent design, more suitable for libraries, bedrooms, offices, high speed rail planes and other public places.  5、Rechargeable Battery: Wireless vertical mouse with built in rechargeable battery for fast charging, supports for Windows 2000, for Windows XP, for Windows 7, for Windows Vista, for Windows 98, for OS X, for Windows ME, for Windows 8, for Windows 10, etc.