Beyond sound. Beyond color. Take your bluetooth headphones everywhere and follow the latest trend thanks to the folding systema and the color touch of your Energy Headphones BT2 Bluetooth. Answer calls and control your music playback with just one click. - Design: Open.- Type: Dynamic.- Frequency response: 20Hz ~ 20KHz. - Total Harmonic Distortion: <1%. - SPL: 93±3dB.- Neodymium magnet. - Bluetooth®:- [Type: Bidirectional. 4.0 Version, class 2.- Working range: 10m.] - Microphone:[- Microphone sensitivity:- 38db ± 3db.] - Battery: [-Type: Lithium polymer. - Capacity: 200mAh. - Charging time: About 3 hours. - Playback battery life: 10 hours. * - Music mode battery life: 10 hours. - Standby battery life: 20 hours. - Charging port: Type-B micro-USB . * The battery life is approximate. A higher volume on the headphones means increased battery consumption. - Energy Headphones BT2 Bluetooth Cyan.- Micro-USB battery charger cable.- Quick Guide. - 170 x 160 x 50mm.- 155g.