Advanced Technology AR-15 Castle Nut Mil-Spec Steel

Upgrade your AR-15 with the Advanced Technology AR-15 Castle Nut, made from durable mil-spec steel for high performance. This black castle nut is compatible with commercial, military, and hybrid buffer tubes, ensuring a secure fit for most AR-15 and AR variants. Please note, it is not compatible with 308 rifles. Enhance your firearm’s reliability with this virtually indestructible accessory.