MBUS 3 Rear Sight — Product Details

The next evolution of the Magpul Back-Up Sight line, the MBUS 3 blends the strengths of the original MBUS and MBUS Pro into a compact, rugged, feature-packed back‑up sight system.

Overview

• Smaller and lighter than previous MBUS models — only 0.55" high (folded), 1.38" wide at its widest point, and ~30 g with hardware.

• Aesthetics inspired by the MBUS Pro, but built from impact‑resistant polymer for extreme durability and low weight.

• Uses spring‑loaded deployment with an ambidextrous push‑button for fast, reliable operation.

• Sits at standard AR height when deployed and includes a windage‑adjustable, rapid‑select rear aperture.

Key Features

• Full‑featured, spring‑loaded flip‑up sight — fast deployment and solid lockup.

• Ambidextrous push‑button for intuitive operation from either side.

• Rapid‑select rear aperture system with windage adjustment for quick transitions between apertures.

• Compact footprint — only 0.55" folded height and 1.38" maximum width; ideal for low installed height setups.

• Impact‑resistant polymer construction — resists operational abuse while keeping weight to a minimum.

• Clamps to most MIL‑STD‑1913 (Picatinny) rails.

• Made in the USA.

Benefits

• Low profile when stowed — reduces snagging and sight‑shadow behind optics.

• Robust enough for hard use but light enough to preserve weapon balance.

• Rapid, reliable sighting solution for co‑witness or backup to optics.

• Ambidextrous controls suit both left and right‑handed shooters.

Available Colors

• Black

• Flat Dark Earth (FDE)

• OD Green

Physical & Mounting Notes

• Folded height: 0.55"

• Maximum width: 1.38"

• Weight: ~30 g (with hardware)

• Height when deployed: Standard AR‑height

• Mount: Clamps to most MIL‑STD‑1913 (Picatinny) rails

Front and side views of the deployed MBUS 3 Rear Sight illustrate the compact dimensions and easy‑to‑use release button; stowed views show the low installed height and minimal profile.