Battery life---Built-in rechargeable 450mAh polymer lithium battery, low consumption, working time up to 10 hours.Convenient button---Convenient operation button can easily control playing or pausing music, answering or hanging up the phone. The exquisite, compact and waterproof design makes B35 a good companion for your cycling journey.High power volume---Use high-power audio amplifier to make the audio volume range larger, and will not affect music playback and phone answering in the noisy environment of high-speed riding.Tight installation---Fix the host with screws to make the host installation tighter and not easy to fall off during high-speed riding.Wide application---The advanced CSR BT 4.1 + EDR chipset provides stable connection, perfect stereo music and hands-free calls for all BT-enabled mobile phones.