Charging one time and it can be working for up to 12 hours. 200 FM transmitting channels to choose, no interference with each other, multiple functions and wide compatibility. HD digital display screen, light weight and portable with volume up function. Ergonomic design makes it comfortable to wear. It is widely applied in teaching, tour guiding, promotion, lecture, meeting, karaoke, singing, home using, KTV and computer. Mic Type: Condenser Wearing Way: Headset wearing Display Screen: LCD Digital display Power Supply: Built-in rechargeable 500mAh 3.7V Battery Receiving Sensitivity: -94dBm Transmitting Frequency: 689MHz-718MHz Frequency Response: 20Hz-20kHz Power: Receiver: greater than equal 95mA; Transmitter: greater than equal 110mA Effective Distance: 40-50m Transmitting Channels: 30 Features: UHF Wireless technology, anti-interference, long distance, high definition, and USB flash disk supported Compatibility: All audio equipments with Mic ports Colour:Black Material:ABS Package Contents: 1 * Wireless Microphone 1 * USB Receiver 1 * USB Cable 1 * 3.5mm Audio Cable 1 * 6.35mm Adapter Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.