Wireless microphone set with receiver

Unidirectional sound Microphone Form Factor Microphone System Item Dimensions LxWxH 8.26 x 5.31 x 1.77 inches Power Source Battery Powered Number of Batteries 2 AA batteries required. (included) Signal-to-Noise Ratio 70 dB Hardware Platform Karaoke Machine AUTO SCAN FEATURE AND ANTI-INTERFERENCE FEATURE: UHF wireless karaoke microphone system equips with auto scan function, which enables wireless microphone & system to search for the least interference channel to pair up with transmitters. It also has lock function to lock selected frequency. High-gain antennas increases anti-interference ability and decreases interference between each channel.