voice by the switch on the plug. *Mic controller and the mic head is adjustable.Function characteristics: Bluetooth Version:CSR4.0Bluetooth Headphone(1) With bluetooth function(2) With Microphone function ????????????????? ? ? ? Output power:0.25W*2Frequency:20-20,000HzTransfer Distance:33ft (10m)Impedance:32 OHM(Ω)Lithium battery capacity:250mAhPlay/Talk time;5-6hoursCase Material:ABSDimensions: Weight: Color:blue,red,black