M1 works as radio earpiece receiver.
Matched with 60DT (transmmitter+receiver) and 60DTR (transmmitter+receiver).
It is used in a single and double transmitter circumstance.
Working mode: Digital QPSK; frequency range: UHF (customizable); channel number: 44CH
Channel interval: 1MHz; working current: 40 mA
Frequency response range: 20Hz-10KHz; distortion: <1%
SNR: 100dB; output/input interface: built-in speaker; battery capacity: 350mAH
Charging current: 260mA; weight: 17g
Effective distance: 150m; accessories: hook and small covering