Rx sensitivity:-113 DBU 1, a receiver 1 1, this product is an underwater entertainment to enjoy life. Input sensitivity: more than 200 mV 2, power adapter a 2, through the wireless the host can bring joy various formats music. SNR: frequency 82 dB 3, product instruction 1 a 3, in the water through the bone conduction way, make the person is in the closed position underwater change, heavy son can play a refreshing, resist fatigue distortion rate: 0.7% or 4, product certificate 1 of 4. In the hearing the bad environment he can improve command safety frequency response: 60 Hz-20 KHz 5, it is the underwater coach's right-hand man, solved the past shout break throat things. Speaker: bone conduction 6, application field: swimming, underwater exploration, underwater ballet, sailing deaf school power supply voltage: DC 3.7 V 7,