MBUS 3 Flip Up Rear Sight by Magpul

The MBUS® 3 Rear Sight is a compact, lightweight flip-up backup sight engineered to provide reliable aiming capability when your primary optic fails. Designed for modern AR platforms, this third-generation MBUS sight features a significantly slimmer profile while maintaining the durability and reliability Magpul is known for.

Built from impact-resistant polymer and designed to mount directly to MIL-STD-1913 Picatinny rails, the MBUS 3 Rear Sight deploys instantly with an ambidextrous push-button. A tool-less windage adjustment system and rapid-select dual aperture allow shooters to quickly adapt to changing distances and lighting conditions.

Key Features & Benefits

Low-Profile, Compact Design
• Slimmer and lighter than earlier MBUS generations
• Stows at approximately 0.55 inches above the rail for minimal interference with optics
• Compact footprint preserves rail space for accessories and optics

Spring-Loaded Rapid Deployment
• Ambidextrous push-button activation for fast flip-up deployment
• Designed for immediate use when optics become unavailable
• Smooth and reliable deployment mechanism

Tool-Free Windage Adjustment
• Windage can be adjusted on the fly without specialized tools
• Precise click adjustments allow shooters to maintain proper zero
• Approximately 0.5 MOA per click with a 14.5" sight radius

Rapid-Select Dual Aperture
• Rotating aperture system offers both large and small apertures
• Wide aperture ideal for close-range or low-light conditions
• Narrow aperture improves precision at longer distances

Durable Polymer Construction
• Lightweight yet highly impact-resistant polymer body
• Engineered to withstand harsh environments and repeated field use
• Maintains durability without adding unnecessary weight

Universal Picatinny Compatibility
• Securely mounts to most MIL-STD-1913 Picatinny rails
• Standard AR sight height for proper alignment with front sights and optics

Specifications

Product Type: Flip-Up Rear Backup Sight
Platform Compatibility: AR-15, AR-10, M4, M16, M110, SR-25
Mounting Interface: MIL-STD-1913 Picatinny Rail
Material: Impact-Resistant Polymer
Weight: Approximately 30 g (about 1.0 oz)
Height Above Rail (Stowed): ~0.55 in
Width: ~1.38 in
Centerline Height (Aperture to Rail): ~1.41 in
Windage Adjustment: ~0.5 MOA per click with 14.5" sight radius
Aperture System: Rapid-select dual aperture
Country of Manufacture: USA