Number of keys: 22 Remote control distance: about 10m Battery type: 2 x AAA (not included) Transmission and control: 2.4G wireless Power consumption: about 10mA (under working condition) Microphone power consumption: about 20mA Supported operating systems: for windows, Android and Mac OS, Linux, etc Size: 157x42x16mm/6.18x1.65x0.63in