ER34615 size D lithium batteries Size: 34.0mm* 61.5mm Nominal voltage: 3.6v Capacity: 19Ah Max constant current: 200mA Max. pulse current: 400mA Operating temperature: -55 - 85 degree ER34615M size D Size: 34.0mm* 61.5mm Nominal voltage: 3.6v Capacity: 14.5Ah Max constant current: 2000mA Max. pulse current: 3000mA Operating temperature: -55 - 85 degree