Out of stock
SKU: EG4971-B
UPC: 810049123000
The Ergo Castle Nut For AR15 Blk is a mil-spec receiver extension castle nut designed specifically for M4-style carbine builds and direct impingement systems. This component is essential for securely locking the buffer tube assembly to the lower receiver, making it a critical part for anyone assembling or servicing an AR-15 platform rifle.
Manufactured from hardened steel and finished with a durable black oxide coating, the Ergo Castle Nut is designed for dimensional accuracy and material integrity. Its fluted design allows for quick tightening and removal using a standard armorer's wrench, facilitating ease of installation. This castle nut is compatible with all mil-spec AR-15 receiver extensions, including M4 and M16-profile carbine tubes.
Installation requires only a castle nut wrench and proper torque technique, making it accessible for both professionals and serious civilian shooters. The Ergo Castle Nut is ideal for law enforcement, military, and civilian applications, ensuring reliability and performance in tactical builds.
WARNING ⚠️ You must be 18 or older to purchase shotgun or rifle ammunition and 21 or older to purchase handgun ammunition and firearms. Please reference our requirements for ammunition orders to "restricted" states HERE. Always make sure you use the correct ammunition for your firearms. Ammo cannot be shipped to a PO Box. Please reference state & local laws before making a firearm or ammunition purchase.
