Product Description Bluetooth:v3.0. Battery, CR2032 button cell. Working voltage, 2. 7-3.2V. Standby time: approx. 3 months. Continuous working time: 20 hours. Working distance: 10Â meters. Safety Tips Warning Read all instructions and warnings prior to using this product. Improper use of this product may result in product damages, excess heat, fire or explosion, for which, you(" Purchaser") will be held responsible. Do not store battery in high temperature environment, including intense sunlight heat. Do not place battery in fire or other excessively hot environments. Do not disassemble this battery or attempt to modify it in any manner. Do not attempt to charge battery using any method, apparatus, or connection other than the US B cable provided along with the product. All batteries have gone through a thorough quality assurance inspection. If you find that your battery is excessively hot or experiencing an abnormal phenomenon, immediately stop all battery use.