Frequency response: 760-790KHz Frequency offset: +- 48KHz Working influents: 110mA Charging port: USB 5V/1A Battery: Li-battery 3.7V/800mA Using hours: 6-8 hours Using distance: 30-40 meters 4 Channels for option Receiver side Frequency response: 760-790KHz Channels: 4 fixed channels 760, 770, 780, 790mHz (can be adjusted for your local frequency 500-980) Working influents: 260mA Charging port: USB 5V/1A Battery: Li-battery 3.7V/800mA, Using hours: 6-8 hours 4 Channels for option Accessories: transmitter(optional: transmitter*2) + receiver + audio cable + Internal recording splitter + output audio cable