Wireless Bluetooth Hi-Fi Stereo ear-plug slim behind the neck Headset with microphon and Audio Dongle and A2DP Audio for MP3 ,MP4, iPod, PC Computer, CD, DVD Player, TV w/Rechargeable Li-battery [Patent No. 200630018610.0 ] Wireless operate the Music Player of PC, Former song/Next song, Volume, Stop/Pause/Play Bluetooth V1.2, class 2.Working range: 15M;Normal Charging Time :2 hours(approx) Operation distance up to 10M;System: Bluetooth; Carrier frequency: 2.5G;Power supply of headphone: Li-Batteries inside, Playback Time:4 to 5 hours. New Bluetooth 3.5mm stereo audio dongle take the output of your CD/DVD players, MP3/MP4 players, PDAs and convert it to streaming stereo audio Full 1 Year Warranty,Dimension: 2.0" L x 0.9" W x 0.6" H (5.2 x 2.3 x 1.4 mm);Weight:0.5 oz (15 g).