The CMC Triggers Multi-Caliber Lower Parts Kit (brand part no. 81500) gives AR-15 builders the small hardware needed to finish a lower receiver, packaged by a company best known for match-grade drop-in trigger groups. CMC built this kit to fit multiple AR-15 caliber variants, so it works whether you’re assembling a standard 5.56 build or a different chambering on the same lower pattern. The kit is explicitly sold without a fire control group or grip, letting builders pair it with their own trigger and grip preferences rather than paying for hardware they’ll swap out anyway.

Key Specifications

• Rated for Multi-Caliber AR-15 platform compatibility, not limited to a single chambering.
• Sold as one complete unit per box (1 per box), ready to open and install.
• Compact package length of approximately 4.8 inches.
• Shipping weight of approximately 0.175 pounds, consistent with a small-parts hardware kit.
• Manufactured by CMC Triggers, a brand best known for precision drop-in trigger assemblies.
• Pairs naturally with CMC’s drop-in trigger assemblies for a full lower build.
• Ships as a complete small-parts kit rather than individual loose pieces.
• CMC Triggers built its reputation on drop-in trigger assemblies, and this kit rounds out the rest of a build around one.

Frequently Asked Questions

Does this kit include a fire control group? No — the fire control group and grip are sold separately, by design, so builders can choose their own.

Is this compatible with multiple AR-15 calibers? Yes, it’s built for multi-caliber AR-15 platform compatibility.

Buy the CMC Triggers Multi-Caliber AR-15 Lower Parts Kit

Finish your AR-15 lower build with a kit from CMC Triggers, a name trusted for precision fire control components. Order it from our Lubbock, Texas gun shop for fast, insured shipping, and see our complete AR lower parts kit selection.