Cherry MW 2100. Device interface: RF Wireless, Movement detection technology: Optical, Purpose: office. Frequency range: 2.4 GHz, Wireless range: 10 m. Wireless receiver interface: USB, Receiver type: nano. Power source: batteries, Battery type: AA, Battery life (max): 366 h. Operating temperature range (T-T): 0 - 40 °C, Storage temperature range (T-T): -40 - 55 °C