Their OPMOD exclusive. This model has quick detach mount and side buttons for a magnifier.
EOTech OPMOD EXPS2 Holographic Reflex Red Dot Sight Includes Blazin' Deal w/ Free S&H — 3 models
EOTech OPMOD EXPS2 Holographic Sights - Limited Edition Red Dot Sights, EXPS2-0OP, EXPS2-2OP, OPMOD, Red Dot Sights, OpticsPlanet Exclusive
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