Feature:1. Support for Windows XP, for Linux, for Vista, for Windows 7 or 8 or 10.2. 22-key wireless numeric keypad, USB plug and play.3. Use time up to 80 hours , keystrokes up to 3 million times.4. Ergonomic design, more comfortable handfeel.5. Scissor foot key cap structure design, fast rebound speed, low delay.Specification:Item Type: 22 Keys Numeric KeypadMaterial: ABSOptional Color: Silver Black or Iron Grey or Rose GoldSupport System: for Windows XP, for Linux, for Vista, for Windows 7 or 8 or 10Number Of Keys: 22 KeysSupport Wireless: 2.4G WirelessKeyboard Life (Keystrokes): 3 Million TimesResponse Speed: 5 MillisecondsWireless Transmission Distance: Approx. 10m or 32.8ftWorking Current or Voltage: 0.25MA 3VBattery Type andamp Capacity: 2 x AAA (Not Included)Use Time: 80 Hours.Package List:1 x Numeric Keypad (Battery Not Included)1 x User Manual 1 x Receiver