EOTech MPO III EXPS2-2 Holosight with G23 3X Magnifier - 2 1MOA Dots Single transverse 123 battery to reduce sight length Shortened base only requires at most 2 3/4 inch of rail space Battery cap and latch are eliminated and replaced with a simple O-ring, tethered cap; better sealing is achieved Battery compartment is now separated from the base to allow it to hover over the delta ring of the rifle Average battery life at brightness level 12 is roughly 600 hours