3LR6 Battery: Nominal Voltage: 4.5V 3 pcs AA size battery in series. Rind dimensions: 62?.5mm Its Capacity lesser than 3LR12,but it is durable,why? Because the rind can be used repeatedly,and you just need to open it and change 3 new batteries when the battery out of energy.(but you'd better read the instruction first when you will do this) More details please see our specification! We supply OEM service,welcome enquiry!