Features: Provide up to 5 hours of music time, 300 hours of standby time. Support 2 in 1, connections of earphone, cellphone, speaker and cars. Full compatibility - Bluetooth 4.1 receiver is compatible with most smart phones. Automatic re-connection: turn on the phone's Bluetooth and the Bluetooth receiver, then Mpow Bluetooth receiver can be automatically paired. 3.5mm auxiliary universal jack - support wired/wireless headphones, earphones, speakers, car speakers and so on. Ideal choice for home or car audio systems. Specifications: Type: Bluetooth Receiver Model: KR105BL Bluetooth receiver Product material: plastic + metal Color: black, white, blue optional Interface type: 3.5mm Bluetooth version: Bluetooth 4.2 Battery: 401020 Battery: 180mAH Talk time: 250 hours Standby time: 300 hours Effective radius: 20 (m) Net weight: Approx 12g/0.4oz Product size: Approx 5.9 * 1.5 * 1.2cm/2.3 * 0.6 * 0.5inch (L * W * H) Package list: 1 * Bluetooth Receiver 1 * 3.5mm Metal Adapter 1 * 20 cm USB Charging Cable 1 * Chinese&English Manual 1、Up to 5 hours of music time, 300 hours of standby time. 2、Support 2 in 1, connections of earphone, cellphone, speaker and cars. 3、Full compatibility - Bluetooth 4.1 receiver is compatible with most smart phones. 4、Automatic re-connection: turn on the phone's Bluetooth and the Bluetooth receiver, then Mpow Bluetooth receiver can be automatically paired. 5、3.5mm auxiliary universal jack - support wired/wireless headphones, earphones, speakers, car speakers and so on.