ER2773B Features Music/call switching， free and relaxed Two-link: can connect two Bluetooth devices at the same time Over length receiving distance， can reach more than 20M in open space without obstacle Inner 170 mA Li-battery， over length battery working time， low power consumption Supports mobile， laptop， iPhone， iPad， MID and so on that with Bluetooth function Bluetooth V3.0 with EDR for superior wireless performance Supports A2DP V1.2， Class 2 Powered by 5V DC General Specs Bluetooth Profiles A2Dp & AVRCP Bluetooth Distance Up to 33 feed (10 meters) away Audio Use with home stereos/speakers， car stereos， headphones etc. by 3.0mm stereo inlet socket Power Supply Inner 170mAh Li-Battery charging via Micro USB cable Operation Time Up to 8 hours music playback or continuous with Micro-USB charger Dimensions 50 x 25.5 x 11cm Package Details Weight: 83.46 g Size: 15.5*10*2.4 cm Package Includes 1x Car Bluetooth Music Receiver，1x 3.5mm Audio Cable，1x 3.5mm Audio Adapter，1x Micro USB Power Cable，1x User Manual，