Volkano Lunar Series Bluetooth Headphones - Black/Silver Bluetooth Folding Headphones with Mic Technical Specs Bluetooth Version?V4.2 chipset:JL profile: HFPV1.5, A2DPV1.2,AVRCPV1.4?GAVDP v1.2, AVDTP v1.2, SPP v1.2, AVCTP v1.3 Bluetooth Distance : Up to 10m Driver Size??40mm Impedence:32? Frequency Range:20Hz-20,000Hz Sensitivity:106±3dB Battery: 3.7V, 250mAh, Charging Time?About 2 hours Charging input:DC5V Worktime: About 6 hours What's in the box 1 x Volkano Lunar Series Headphones Blk/Slv