Replacement Lithium-Ion (Li-ion) rechargeable battery for iOptron AZ Mount Pro mount. Features: Assemble with 6 cylindrical 18650 high quality 3.7V Li-Ion rechargeable battery pack Capacity 4400mAh Voltage 11.1V, peak at 12.6V No memory effect Longer storage life than NiMH Batteries Built-in IC chip will prevent battery pack from over charge, over discharge and prolongs battery life WARNING: Li-ion battery is very sensitive to charging characteristics and may explored or burn if mishandled Charge only use a charger designed for this battery Do not charge the battery below 0C Do not dispose in a fire Disposal the battery according your government regulation Specifications Battery type: Lithium-Ion rechargeable battery, 6 X 18650 Capacity: 4400 mAh Output voltage: 11.1V (peak at 12.6V) Dimensions: 2.75"X2.15"X1.5" (68 X 55 X38mm) Weight: 10.2 oz (290g) Charging voltage: 12.6V Warranty: 30 days limited