Magpul Battery Storage Core - Made in the USA, The MIAD/MOE Battery Storage Core is an internal core unit for the MIAD as well as the MOE, MOE+, MOE-K2, and MOE AK Grips. It is designed to hold two (2) AA type batteries in a self-contained, water resistant unit. Included internal spacer provides rattle free storage of either (2) AAA or (2) N size batteries (commonly used for EOTech sights). Rubber cap has two sides with marking to identify "spent" batteries and can be opened with a push of the thumb.