The CSAT Tactical sight set features the standard XS tritium front strip sight post and the CSAT Rear aperture. The CSAT rear sight was designed by Paul Howe to allow the operator to accurately engage targets from 7yds to 100yds without moving hands to flip sights or have a second set of sights. The notch on top is used for targets at 7yds with a sight picture similar to pistol sights. The aperture is used for targets at greater distances and is used as a normal AR-15 rear sight. Front Tritium stripe provides quick acquisition with it's easy to see .105" diameter. Sights fit A2 housing.