Stern Defense 9mm Bolt Features The Stern Defense 9mm Bolt is machined from 8620 AISI steel a material chosen for its strength and durability in a part that experiences repeated cycling and impact during firing. A Mag-Phosphate finish is applied for corrosion resistance and reduced friction during operation. This bolt is designed to fit into both Mil-Spec and Glock pattern upper receivers giving builders flexibility depending on which magazine type their lower is configured to accept. A custom 4140 billet extractor is incorporated into the design to provide superior ejection reliability compared to standard components. The bolt incorporates a design catering to single stage triggers with short resets and is also compatible with the JP silent capture spring system for smoother cycling. It works with the Law Tactical folding stock adapter giving builders the option to add a folding stock to their 9mm platform. Fully assembled out of the box the bolt includes the firing pin spring retaining pin extractor and extractor spring along with proprietary center and roll pins. Made in the USA this bolt is a dependable choice for anyone building or repairing a 9mm AR15/M16 pattern firearm using Colt SMG or Glock magazines. Stern Defense 9mm Bolt Specifications Manufacturer: Stern Defense Caliber: 9mm Material: 8620 AISI Steel Finish: Manganese Phosphate Compatible Hosts: AR15 / M16 Glock Pattern Uppers Magazine Compatibility: Colt SMG Glock Weight: 15.5 oz Available At: GrabAGun