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September 16, 2026CMMG AR-15 Zeroed Lower Parts Kit Gunbuilder’s Kit
$84.36
CMMG AR-15 Zeroed Lower Parts Kit Gunbuilder’s Kit
4 in stock
Customization is endless with the AR15 platform which is why the CMMG ZEROED Mk4/AR15 Gunbuilder’s Kit includes all of the essential parts except the most commonly upgraded ones: Trigger Guard Fire Control Group and Pistol Grip. Check out our interactive install walkthrough video below or read the CMMG Resources LPK Install article for an in-depth breakdown. All parts meet or exceed mil-spec. All installation hardware included.
Kit Includes:
- Bolt Catch Plunger Spring & Roll Pin
- Trigger/Hammer Retaining Pins
- ZEROED 60°/90° Adjustable Ambi Safety Detent & Spring
- ZEROED Ambi Magazine Catch & Spring
- ZEROED Magazine Release Button
- HD Pivot/Takedown Pins Detents & Springs
- Buffer Retainer & Spring
| UPC | 810097502314 |
|---|---|
| Manufacturer | CMMG |
| Manufacturer Part Number | 55CA6BA |
| Shipping Weight | 0.12 |



