Tapco TAP22060 Castle Nut Steel Black Anodized AR Platform

The Tapco Castle Nut (TAP22060) is a precision-engineered steel retaining nut built to Mil-Spec standards for AR Platform rifles. This black anodized castle nut is the component that threads onto the buffer tube to lock it securely into the lower receiver, making it a critical part for any AR-15 build, repair, or armory spare.

Manufactured from steel with a durable black anodized finish, this castle nut resists corrosion and wear from repeated installation and removal. It features the standard castle-cut profile with evenly spaced notches around its circumference, allowing it to be torqued into place with a standard castle-nut wrench or armorer's tool. The transverse slot accepts the buffer retainer spring and detent to keep the buffer captured during disassembly.

Designed as a direct replacement or spare for AR Platform rifles using a mil-spec buffer tube, the Tapco Castle Nut is a straightforward, no-frills part suitable for new builds, lower receiver assemblies, or armory stock. The black anodized finish blends cleanly with most black receivers, buffer tubes, and end plates.