Features: Pro Series Flip-Up Front sight is a low profile spring loaded front back-up sight that flips-up and deploys with a push of a button. Features an A2 front sight post that is fully adjustable for elevation. Front sight height is designed for handguard rails, monolithic receivers, and gas blocks that are at the SAME height as the AR receiver Picatinny rail. Dimensions: 2.4"L X 1.1"W X 0.8"H Weight: 2.0 oz. Aluminum main body with steel A2 front post. Mounts onto Picatinny Mil-STD 1913 rails, mounting tool included. US. PAT. 9976834