The Magpul Grip Core MIAD/MOE CR123A Battery Storage Core is the internal core unit for the Magpul MIAD, MOE and MOE-K2 Grips. The core was designed to hold two (2) CR123A lithium type batteries in a self contained, water-resistant unit. Rubber cap is captured to the unit and can be opened with a push of the thumb. Not recommended for use with the MOE+ grip due to its slightly smaller internal dimensions required by the rubber overmolding. Made in the USA.