Product Features:? 1. Bent ear hook， allowing a more comfortable wearing headphones and higher quality calls ? 2 three-ear earplugs choice， so you feel more comfortable ? 3. Noise cancellation， allowing more perfect sound quality ? 4.LED indication ? 5 volume plus or minus keys ? 6 Power / Mute button Product parameters:? Bluetooth specification: V2.1 EDR ? Transmission frequency: 2.4GHz ? Speaker power: 1mW (Max 3mW) ? Operating voltage: 3.6V-4.2V ? Transmission distance: 4M ? Charging time: Max.3H ? Voice calls: 7 ? Lithium Battery: 5V， 250mah ? Product Dimension: 14 * 19 * 3cm ? Weight: 113g ? Color: Black Package:? 1 * Bluetooth headset ? 1 * USB cable ? 3 * earplugs