This sight includes both low profile spring loaded front and rear back up sights that deploy with a push of a button. The Front sight features an A2 front sight post that is fully adjustable for elevation and is designed for handguard rails, monolithic receivers, and gas blocks that are at the SAME height as the AR receiver Picatinny rail. The Front Sight Dimensions are 2.4"L X 1.1"W X 0.8"H, Weight: 2.0 oz. and the Rear Sight Dimensions are 2.4"L X 1.2"W X 0.8"H, Weight: 2.3 oz. This sight mounts onto Picatinny Mil-STD 1913 rails, mounting tool included.