Description
AR-15 notched crown castle nut in black billet aluminum. It secures the carbine-length receiver extension (buffer tube) and end plate to the lower receiver, with standard notches sized for both your armorer’s wrench and a staking punch. Aluminum construction saves a small amount of weight versus a steel castle nut — a straightforward part on any AR-15 lower build.
Features:
- Billet aluminum construction, black anodized finish
- Crown (notched) castle-nut design
- Standard armorer’s-wrench notches — fits industry-standard wrenches
- Staking notches on the flat face to lock the nut against the end plate
- Lighter than a comparable steel castle nut
Secures a carbine receiver extension and end plate on a mil-spec AR-15 lower. Aluminum is softer than steel — stake the nut with a punch after torquing so it cannot back off under recoil. Verify your buffer tube uses standard mil-spec threads (1.185″-18) before installing.
