Castle Nut Vector Optics AR

The AR castle nut from Vector Optics is meant to lock an AR-style buffer tube so it stays secure and can’t twist relative to the rifle. It can also be used to lock the receiver end plate to perfectly align the stock with the rifle.

This Ergo AR castle nut is made from black coated steel and is knurled so it can be tightened by hand, but also features notches to accommodate the use of a C-spanner.