The CMMG AR15 Buffer Tube Castle Nut is a replacement or spare castle nut designed to secure the buffer tube to the lower receiver on AR-15 pattern rifles.
- Part Type: Castle Nut
- Compatible Firearms: AR-15 Platform Rifles
- Material: Steel
- Finish: Phosphate or Black Oxide (manufacturer standard)
- Installation: Armorer’s Wrench Required, Staking Recommended
- Includes: (1) Castle Nut
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