Very slim, extremely light weight (37 g) rechargeable battery with high energy density. Each cell outputs a nominal 3.7V at 1800mAh. Comes terminated with a standard 2-pin JST-PH connector with a 2 mm spacing between the pins. Includes a built-in protection against overvoltages, overcurrents and minimum voltage. Recharge only by connecting the mCore card via USB cable or with a charger specifically designed for lithium-ion batteries. 60 x 50 x 5 mm.