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Product Description
The CMMG MK4 Receiver Extension Castle Nut is a replacement castle nut designed to secure your receiver extension (buffer tube) for AR-15 platforms. Manufactured for dependable fit and function, it features a durable matte black finish for a clean, corrosion-resistant look that complements most builds. Ideal for maintenance, repairs, or upgrades, this castle nut helps keep your buffer tube assembly properly retained under hard use.
Product Highlights
AR-15 castle nu…
Specifications
- Manufacturer:
- Cmmg
- Category:
- buffer-tube
- Platforms:
- AR-15
- Weight:
- 1.6 oz
- UPC:
- 815835017426
- MPN:
- 55CA9CB
- Required Component:
- Yes
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$17.49
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