Specification:

Frequency range: 640-690MHZ

Microphone Type: Condenser

Directivity: Unidirectional

Transmitter working current: about 100MA

Receiver working current: about 80MA

Microphone size: 97*50MM

Charging interface: USB5V/1A

Transmitter lithium battery: 3.7V/800MA

Receiver lithium battery: 3.7V/700MA