Bluetooth V4.1 wireless audio transmission, true HD high fidelity sound. DPS noise reduction technology, filtering ambient noise, the call effect is clearer. The battery capacity of 70 mAh allows a play time up to 4-10 hrs with a quick charge of only 1-2 hrs. Innovation of bluetooth technology. UV surface treatment process which is top grade and textured, 3 sizes of silicone ear caps to adapt your earhole, please choose suitable ear tips and wear your headphone tightly when you are running or cycling, it will help you reduce the annoying wind noise. Ergonomically designed flexible ear hooks with gel flex silicone earbuds to ensure your headphones stay comfortably firm in place to guarantee fatigue free ears and tangle free comfort. Guarantee: If you have any problem, please feel free to contact us first, we will do our best to solve it and provide you with good service to give you a perfect shopping trip. Built-in 70mAh Lithion-ion battery.