Overview: Trust Fire Protected Rechargeable Li-ion Batteries -Gray (4-Pack) Precise digital protection circuit built-in The voltage of full charge & cut-off discharge is 4.2V & 2.75 V Don't heat, incinerate or reverse polarity Specification: Trust Fire 10440 600m Ah 3.7 V Dimension (CM):4 x 1 x 4.5 Weight (Kg):0.0349