Crafted from durable 8620 AISI steel the Stern Defense 9mm NIBMag Phosphate Hybrid Bolt is engineered for precision and reliability in your AR15 setup. Its NIBMag phosphate hybrid finish ensures enhanced durability and resistance to wear making it a standout choice for enthusiasts and professionals alike. Designed to fit seamlessly into MilSpec and Glock-pattern upper receivers this bolt is versatile enough to function with both Colt SMG and Glock magazines. Fully assembled it includes essential components like the firing pin extractor and proprietary center and roll pins. The innovative bolt design supports single-stage triggers with short resets providing a smoother shooting experience. Upgrade your AR15 with a bolt that combines strength compatibility and performance.