Eotech HWS EXPS2 Green Holographic Sight. Accelerated accuracy that takes up just 2.75in of rail space. Our Model EXPS2-GRN holographic sight features green-reticle technology-approximately 5X easier to see than red in daylight-and leaves plenty of rail space for adding a magnifier and other attachments. Durable, lower third iron sight co-witness, and ergonomic, side-button adjustment all in a rock-solid unit with an adjustable, quick-detach locking lever.