Yankee Hill Machine Flip-Up Rear Sight AR-15 Flat-Top Aluminum Matte

The Yankee Hill Machine flip-up rear sight for AR-15 flat-top receivers gives you a no-nonsense backup aiming solution that stays out of the way until you need it. Built on a steel base with an aluminum stem and matte finish, this compact sight mounts to any Picatinny rail and folds down to just 0.840 inches, so it won't interfere with your optics or compromise your sight picture. Whether you're running a red dot, magnified scope, or building a co-witness setup, this sight locks securely in the deployed position and releases just as quickly with a thumb screw—the kind of reliable simplicity that matters when it counts.

Yankee Hill Machine engineered this sight to pair seamlessly with standard M16/M4 front sights and their full lineup of front sight options, so you can build a complete backup iron sight (BUIS) system that works together. The 1/2 M.O.A. adjustment and standard peep aperture give you the precision you'd expect from a quality rear sight, without unnecessary features or weight. It's the kind of gear that sits on your rail doing nothing until the moment your primary system fails—and then it's there, ready to go.

This is a practical choice for hunters, tactical shooters, and anyone who understands that redundancy isn't paranoia—it's smart planning. The aluminum construction keeps things light, the steel base absorbs recoil, and the compact profile means you're not sacrificing rail space or sight radius. If you run an AR-15 and want a proven backup sight that doesn't compromise your rifle's ergonomics or aesthetics, this one earns its place on your receiver.

Key Features

• Compact folded height of 0.840 inches—minimal footprint on Picatinny rail
• Steel base with aluminum stem for durability and light weight
• Quick-release thumb screw for fast deployment and stowage
• Locks securely in the deployed position
• 1/2 M.O.A. adjustment for precision aiming
• Standard rear peep aperture
• Co-witnesses with standard M16/M4 front sights
• Matte finish resists glare and blending
• Compatible with all Yankee Hill Machine front sights

Specifications

Frequently Asked Questions

Will this rear sight co-witness with my front sight?

Yes. The Yankee Hill Machine flip-up rear sight is designed to co-witness with standard M16/M4 front sights and all Yankee Hill Machine front sight models, so your backup irons will align properly when deployed.

How small does this sight fold?

When folded down, the sight measures just 0.840 inches from its highest point to the top of the upper receiver, leaving your rail space and optics footprint nearly uncompromised.

What kind of rail does this mount to?

This sight mounts to any Picatinny rail on your AR-15 flat-top receiver, making it compatible with virtually any modern AR platform and rail system.

Is this a good backup sight for a primary red dot or scope?

Absolutely. The compact folded profile and quick-release thumb screw make it an ideal backup iron sight (BUIS) for shooters who run optics as their primary aiming system but want a proven iron sight fallback.