Enhance the reliability and performance of your AR with the Presma Aluminum Castle Nut, designed specifically for .223/5.56/.308 buffer tube receiver end plates. Manufactured from high-grade aluminum, this durable and lightweight nut ensures a secure fit and optimal function, suitable for both professional and recreational use. Precision-engineered for AR platforms Corrosion-resistant blue finish Easy installation with standard tools Compatible with various buffer tube systems Trust in Presma for a superior assembly that maximizes the performance of your firearm.