Phase 5 Weapon Systems UMS Universal Mini Stock AR-15 6061-T6 Aluminum Black

The Phase 5 Weapon Systems UMS (Universal Mini Stock) is a compact, fixed buttstock solution offered in New Condition for the AR-15 platform. Machined from a single billet of 6061-T6 aluminum and finished in black MIL-A-8625 Type III Class 2 hard coat anodizing, the UMS delivers a rugged, lightweight stock that shrugs off hard use while keeping your rifle's overall length trim.

The Universal Mini Stock measures just 5" long overall (5 x 1-3/4 x 2-1/4 inches) and tips the scales at only 5.7 oz, making it an ideal upgrade for builders running shorter AR-15 pistol or SBR configurations where every ounce and inch matter. Despite its minimal footprint, the UMS provides a stable cheek weld and slips easily into tight storage or transport cases.

Phase 5 designed the UMS for broad buffer-tube compatibility. It fits Mil-Spec 6-position carbine receiver extensions, the Phase 5 HexOne and Hex-2 buffer tubes, and most cylindrical buffer tubes with an outside diameter between 1.10" and 1.25". Installation is a simple slip-on fit onto the receiver extension, secured by the standard castle nut and end plate (sold separately).

Whether you're building a lightweight defensive carbine, a packable truck gun, or just want to shave bulk off an existing AR-15, the Phase 5 UMS gives you a low-profile fixed stock option without sacrificing the durability you'd expect from a solid billet aluminum component.