SPECIFICATIONS Bluetooth Versionv4.2+EDR Supported ProfilesHSP,HFP, A2DP, AVRCP Frequency range2.40 GHz – 2.48 GHz Frequency response20Hz-20KHz Output Power3mW x 2 Input charging powerDC5V Wireless working distance≦10M Battery110mAh Charging time≦3Hours* Playback time16-20Hours* Standby time≧150Hours* MicrophoneBuilt-in Weight135g SO LIGHT, YOU’LL HARDLY KNOW THEY’RE THERE The Enter GO Powerbeat Flex wireless neckband headphones are