New Fully CNC Machined Modified Bolt Breach face machined to correct head space (.044'). Rear face machined to correct firing pin protrusion (.040'). Power Custom Titanium Extractor Claw installed and tuned. Rear of bolt radiused for easier cocking. Beveled Power Custom Titanium firing pin. Firing pin is pinned so, it keeps it from coming up in the action. Drops right in. Designed to work with the CST Last shot hold open. You will not need a modified magazine for last shot hold open will work with our bolt.