The MS-D14EN Li-ion Rechargeable Battery Holder from Nikon is a replacement Li-ion battery tray for the Nikon MB-D14 Multi-Power Battery Pack (Grip). It holds one rechargeable EN-EL15 Li-ion batteries and slides into the base of the battery pack. The MB-D14 Battery Pack is compatible with the Nikon D600 DSLR and is powered either by EN-EL15 Li-ion battery packs or by AA batteries. For each type of power source there is a separate battery holder.