Specification This is the GENAI-B1 Wireless Mini Bluetooth headset,The B1 smart Earphone bluetooth is a CSR4.0 Popular Wireless Bluetooth earphone.Built in HD MIC And Music stereo.that can be used and compitiable 99% bluetooth Device anywhere all over the world. you gain an amazing communication device that works like a cell phone on your smartphone.Is a very neutral headset products, excellent performance of wearing comfort, voice can ensure people to listen to pop music on demand, and appearance design also seize the eye of a lot of men and women, The top quality and Fashion design is important reasons of this Earphone will definitely popular. both at home or outdoors,During Driving,Travling,Walking etc.either long or short time, can choose this headphones. Feature: 100% brand new and high quality. Outstanding Voice quality. Build in Micphone,easy free Talk. Size:5.38 x 1.4 (L x W) . Soft in Ear Earbud Design,no need earhook also can use. Fashion Design .Easy to carry. Effective range:10 metres farthest. Talk Time:Up to 8 hours. Standby time:up 160 hours. Weight:10g. Bluetooth Version: Bluetooth V4.0+EDR. How to use: Press the power button(the Blue part) for about 5 seconds until blue-red light flashes quickly. Then turn on the Bluetooth function of ur cell phone Connect it with B1. If You want to connect 2 phones Just Switch of the Bluetooth Device and again Connect with New Phone with STEP 1 & 2 Now you are ready to use Bluetooth with both phone. 1 call at a time.