[only one left ]Wireless Bluetooth Hi-Fi Stereo Headphones with microphone and Audio Dongle for MP3 Players iPods and Computers Bluetooth Stereo Audio Hi-Fi Dongle 3.5mm Jack for MP3 iPod PC,Bletooth Version:V1.2, Class 2 Operation distance up to 15M.Power supply of headphone: Li-Batteries inside;Support A2DP(Advanced Audio Distribution Profile).Carrier frequency: 2.5G Wireless operate the Music Player of PC (Control on earphone) Battery:Rechargeable Lithium Polymer,120mah, DC 3.7v,Charger:5.0~ 5.8 V, 300mA, Charging Time:2 hour Operating Frequency Band:2.402~2.480Ghz Spectrum,Music Playback Time:Up to 4 to 5 hours.