The MBUS Pro is an all-steel back up sight that delivers maximum functionality and strength with minimum bulk. The tool-less elevation adjustable front sight mounts on all 1913 Picatinny rail mounting applications, including rail height gas blocks. Positive detents keep the MBUS Pro at standard AR sight height when deployed, but low profile when stored. The narrow width is compatible with most IR aiming laser and light installations. Steel, rectangular sight post selectable between Match and Standard widths: .04" Match width for increased precision or .06" Standard width for maximum visibility.