Li-ion Battery: 3.7V/150mAhCharging Voltage: DC 5V1xSet-in rechargeable Li-ion battery, long stand-by and working .Equipped With Bluetooth 4.1 technology, it is compatible with most kinds of smartphone, providing efficient and convenient communications in the riding.Bluetooth Range: 10 metersBattery capacity:150mAh battery.This item is a helmet-in headset. It should be put into the helmet to fix tightly. With 2 soft and comfortable cushions, it will not cause much pressure to your ear if you wear it for a long time. It has a built-in microphone so you can answer phone call if there is a call coming without taking your hand.Bluetooth Version: 4.1+EDRPackage Size: 15x10x2.5cm/5.9x3.9x0.9inchWorking Time: About 8HStandby Time: About 160HPlease do not turn up the volume too loudly in driving.Helmet Bluetooth Headset speakers make you enjoy voice and music from your cell phone.Material: PlasticUser Manual1xUSB Charging CableCharging Time: About 2HColor: BlackFrequency: 2.402-2.480GHzHands-, built-in microphone enables you to answer phone without holding your phone during driving.1x