Bluetooth Headset,Anbes Dual replaceable Battery Music V4.1 Bluetooth Wireless Sports Gym Excercises Sweatproof Earbuds Noise Cancelling In-ear Headphones With Mic for Smartphones Devices (Black) A new design concept, bluetooth V4.1, support the multipoint connection CSR high-end chip solutions, more humanized design Support the replacement battery, include a complete set of 2 batteries 100 Days Ultra-long Standby Time,up to 8 hours using time Ears natural curve design,comprehensive fit your ears,wear comfortable,no discomfort