Magicshine MJ-6096 4 Cell Bike Light Battery, 5200mAh Li-ion Waterproof Rechargeable Bike Light Battery for MJ-902, Round Plug, Cable tie, Velcro Strap, Silicone Non Slip Pads Magicshine Rechargeable Bike Light Battery Pack MJ-6096, 4 cell 7.2V 5200 mAh capacity. Compatible with all Magicshine bike lights with round plug, Comes default with MJ-902. Recommend only for MJ-902/902B and MJ-900/900B The battery is more ergonomic and straps neatly to your frame using two nylon straps The new waterproof battery compartment design and high quality and large area silicone non-slip mat All Magicshine batteries include BMS with over-charge, over-discharge, over temperature and short circuit protection meaning you can be sure that your Magicshine battery is safe to use and charge.