New Rechargeable Battery 02-850901-02 For Topcon GR5/GR3 GNSS Receiver Voltage: 7.2V Capacity: 3900mAh Battery for Topcon G.P.S GR3 GR5 Providing high quality power,long life,reliable quality,long working hours etc With PTC protection device, having the function of preventing overcharge,discharge,over current(short circuit),overheating Note: Please charge the battery once when you receive them. Battery products may be damaged if not charged for a long time, please charge the battery at least once every 2-3 months.