The Luth-AR lower parts builder kit supplies the small parts needed to finish a .308 / AR-10-pattern lower receiver, in a builder configuration that leaves out the fire-control group. You supply your own trigger, hammer, and disconnector, which lets you choose the fire-control group you want. Features: .308 / AR-10-pattern lower parts kit Fire-control group NOT included - supply your own trigger, hammer, and disconnector Includes trigger guard, magazine catch, and bolt catch Includes safety selector Includes takedown and pivot pins Includes the associated springs and detents AR-10 / .308 lowers come in different patterns - confirm whether your receiver is DPMS or Armalite pattern before ordering to ensure correct fit.