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AR Parts Notice - State/local restrictions may apply in CT, DC, IL, MA, NJ, NY, or WA. Customers must review our Shipping Policy prior to ordering.
ZEROED Lower Parts Kit, AR15, Gunbuilder's Kit
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.
- 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