Please charge with a special charger for battery.If you have any questions, please contact us economical and practical. highly cost effective. Battery Specifications: Voltage: 3.7V Capacity: 3400mAh Size: 70.2 x 19.7 x 19.7mm Type: Li-ion, Weight: 65.0g Compatible Model: * HMT-1 * B1200G * CommWear HMT-1 Battery Part Number: * B1200GDon’t worry, if you have any questions before or after sale, you can contact me by email at any time, and we will reply as soon as possible. We are a professional battery manufacturer, Certificated with UN38.3, MSDS, ISO9361, RoHS, CE. Replacement battery Part Numbers: B1200G. Specifications: Voltage: 3.7V, Capacity: 3400mAh, Size: 70.2 x 19.7 x 19.7mm, Type: Li-ion, Gross Weight: 65.0g. Replacement battery Compatible with Models: HMT-1 B1200G CommWear HMT-1.