Bluetooth Specification:V1.2,CSR Frequency:ISM 2.402-2.480GHz Support file:Hands-free & Headset Profile RF Output Power:-6 to +4dBm RF sensitivity:> -75dBm Distance:Within 10 meters Indicator:LED (blue &red) Talk time:480minutes Standby time:200 hour Battery:Built-in rechargeable lithium battery Transmission Power:SBC Max. 200kbps, 48.000kHz,16bit Audio code: Stereo Audio Temperature:-10 to 45'C Audio frequency output power:(RL=32 ohms) 2.5mW Audio frequency range:20Hz to 22kHz Charging time:2 hours Box Size:14.5*10.2*5mm Qty/Ctn:50pcs/ctn Measurement:75x22x28CM(LXWXH) Accessories:Bluetooth headsets/charger/manual