A4Tech RP-650Z. Device interface: RF Wireless, Movement detection technology: Optical. Wireless range: 2 m. Battery technology: Nickel–Metal Hydride (NiMH), Battery type: NiMH AA, Current consumption: 1400 mA. Compatible operating systems: Windows98/ME/2000/XP(X64)/2003(X64)/MCE2005/Vista X86&X64Outbox