Description
The Strike Industries Tribus Enhanced Castle Nut & Extended End Plate is an AR-15/AR-10 lower receiver upgrade that combines an anti-rotation castle nut with an extended end plate into a single drop-in assembly. The castle nut is machined from steel and the extended end plate from aluminum, giving the Tribus a lightweight but rugged profile on any mil-spec or aftermarket AR lower.
Engineered to address the long-standing shortcomings of standard castle nuts and end plates, the Tribus features an innovative anti-rotation design that holds the nut securely in place without staking. The integrated extended end plate is shaped to keep the buffer tube from pinching the shooter’s hand when a sling is in use, and it adds three quick-detach (QD) sling mounting points – the traditional 6 o’clock mount plus two additional mounts on the left and right sides for full ambidextrous sling attachment.
Finished in a corrosion-resistant Flat Dark Earth (FDE) anodized coating, the Tribus installs as a true drop-in replacement for the factory castle nut and end plate, making it a straightforward upgrade for both new builds and existing rifles. Approximate weight is 2.2 oz.








