The CMMG Mk3 Carbine Receiver Extension and M4 Stock Kit includes all the essential components for your next AR lower build. Featuring the M4 buttstock, known for its lightweight yet durable design, this kit provides a reliable foundation for your lower receiver group. Simply combine it with your choice of Lower Parts Kit to complete your setup, ensuring dependable performance and comfort in the field or on the range.

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These items are controlled by the U.S. Government and authorized for export only to the country of ultimate destination for use by the ultimate consignee or end-user(s) herein identified. They may not be resold, transferred, or otherwise disposed of, to any other country or to any person other than the authorized ultimate consignee or end-user(s), either in their original form or after being incorporated into other items, without first obtaining approval from the U.S. government or as otherwise authorized by U.S. law and regulations.

WARNING: Handling firearms or firearms parts can expose you to lead and other petroleum products known to the State of California to cause cancer, birth defects, or other reproductive harm. Wash hands thoroughly after handling. For more information go to www.p65warnings.ca.gov (CA Health and Safety Code Section 25249.6).