This is a TROY Sight known as the BattleSight, model SSIG-DOA-RFBT-00.
Advanced design" superior sighting and BattleReady(TM) toughness define Troy Industries' Di-Optic Aperture (DOA(R)) Folding Rear BattleSight(TM). These sights provide lightning fast target acquisition and are manufactured to exceed military specs. The optically engineered apertures center your eyes instantly and effortlessly providing a clearer target picture than with round apertures. The sights feature two settings" one for up to 300 meters and a second for up to 500 meters. This versatility makes the DOA ideal for military" law enforcement and home defense applications. These advanced sights have been extensively field-tested and" like all Troy Industries products" are BattleReady.
Features:
Faster target acquisition with Di-Optic Aperture
Increases accuracy to 550m
Quick install and easy to adjust
.460 profile when folded;Protected adjustment wheel