Cherry Keypad Cherry EN 21keys PS2 CrPf Numeric. Device interface: RF Wireless. Movement detection technology: Uses mechanical keys from our ML series with high-precision key action, Button functions: 4 additional user-programmable function keys, can be labeled individually. Cable length: 1.75 m. Keyboard dimensions (WxDxH): 90 x 132 x 36 mm, Keyboard weight: 260 g. Operating temperature range (T-T): 0 - 50 °C