The Yankee Hill Machine .300 Blackout AR-15 Dust Cover Assembly (Yankee Hill Machine part no. YHM-111-300) is a complete, caliber-marked replacement for the flap that shields your AR-15’s ejection port from dirt and moisture between shots. Yankee Hill Machine stamps this cover from steel and marks it .300 AAC Blackout, so it doubles as a quick visual reference for which upper is chambered for what on a multi-caliber build. Unlike a bare cover alone, this listing is a full assembly, so you aren’t left sourcing small hardware to finish the install. It’s built to the standard AR-15 ejection port opening, making it a straightforward swap on a mil-spec or most aftermarket uppers.

Key Specifications

• Stamped from steel for a durable, factory-style dust cover.
• Laser-marked .300 AAC Blackout, a handy visual cue on a multi-caliber build.
• Sized for standard AR-15 upper receiver ejection ports.
• Ships as a complete assembly with the pivot rod, retaining clip, and spring, so it drops in without sourcing extra hardware.
• Measures a compact 3.05 inches wide by 0.3 inch thick, matching the stock AR-15 ejection port opening.

Frequently Asked Questions

What’s included with this dust cover? It ships as a complete assembly with the cover, pivot rod, retaining clip, and spring, so it drops in without sourcing extra hardware.

Will this fit my .300 Blackout AR-15? Yes, it’s caliber-marked for .300 AAC Blackout and sized for standard AR-15 upper receivers.

Buy the Yankee Hill Machine .300 Blackout AR-15 Dust Cover Assembly

A caliber-marked dust cover is a small detail that pays off the moment you’re juggling more than one upper, and this YHM assembly drops in with everything you need already included. Order from our Lubbock, Texas gun shop and it ships fast to your door, along with more AR-15 dust covers and upper parts.