18V 3.6AH for Black and Decker battery HPB18 Firestorm FS180BX FS18HV FS18ID Cordless Power Tools Battery Type: NI-MH, Voltage: 18V, Capacity: 3600mAh No memory effect. Can be charged or discharged as needed without loss of capacity. Compatible with replacement Black&Decker 18v power tools:FS18HV, FS18ID, FS18PS HPB18 HPB18-OPE 244760-00 The third prong (temp. sensor) enables fast charge mode (approx. 3 amps instead of 1amp; full charge in about an hour or less) . The exposed metal square is for temp sensor on generic chargers. All of the products are CE FCC, ROHS certified, tested by manufacturer to match OEM products and exported all around the world.Longer Lasting&Battery Safety. GERIT BATT 30 days money back and 1 year manufacturer warranty guarantee and 24 hours online service