CMMG Gunbuilder Lower Parts Kit MK3 - 38CA61A

The 308 version includes LR308 takedown and pivot pins as well as an improved bolt catch.  The 308 kits also include a bolt catch screw in place of the AR-15 pin. Parts list includes: Takedown pin, receiver pivot pin, takedown pin detent (2), takedown pin detent spring (2), hammer and trigger pin (2), safety selector, selector detent, magazine catch, magazine catch spring, magazine release button, bolt catch, bolt catch plunger, bolt catch spring, bolt catch spring pin, buffer retainer and buffer retainer spring. Mfg: Cmmg