The Nikon BL-5 Battery Chamber Cover is an add-on accessory that enables Nikon EN-EL18a batteries to be used in compatible battery grips for additional functionality. Key features include:

• Compatible with MB-D18, MB-D17 & MB-D12 Battery Grips
• Adapts EN-EL18a Batteries to the Above-Mentioned Grips
• A-La-Cart Option. Just The Battery Chamber Cover!
• Battery, Charger & Battery Grip Not Included!