The MBUS Pro. The all-steel back up sighting solution that delivers maximum functionality and strength with minimum bulk at a price that's even smaller than its size. The dual aperture, windage adjustable rear and no-tool, elevation adjustable front excel in all 1913 Picatinny rail mounting applications, including rail-height gas blocks. Will not regulate with low profile or standard height gas blocks. Positive detents keep the MBUS PRO front and rear at standard AR sight height when deployed, and so low when they are stowed that you'll never notice them until they're needed. Narrow width front is compatible with most IR aiming laser and light installations for the p Mfg: Magpul SPECS: All steel construction Elevation adjustment knob - no tools required Positive detents in both the up and down positions .432" height above rail at tallest point when stowed Standard AR sight height when deployed Stowed footprint cove