The Nikon EN-EL 18a is a 2500 mAh Rechargeable Li-ion Battery that is used to power the D4s and D4 Nikon D-SLR cameras.
The EN-EL18a Li-ion Battery can be charged using either the MH-26a or MH-26 Battery Chargers.
The BL-6 Battery Chamber Cover must be used with the EN-EL18a battery.
