Quick Detachable Front Sight with Adjustable A2 Square Post Assembly to Fit All Picatinny/Weaver Style Rails. Equipped with Locking Retention Thumb Nut and Flip-up Posi-lock Design to Guarantee Zero in the Most Extreme Combat Condition. Precision Elevation Adjustments to Enhance Shooting Accuracy. Profile Designed for Installation on Gas Block. Material: Aluminum Weight: 3.1 oz Rail Type: Picatinny Weaver Length: 1.1 inch Width: 1.9 inch Height: 2.1 inch