piston with install screw (piston head not included).
3, changeable rear plate.
4, rear sight screw.
5, Steel hammer and stainless steel rotor.
6, New design Hammer, Sear and firing pin spring.
7, Steel level with SKD11 60HRC pin.
8, Steel level spring *2 ( 1 spare).
Guide:
http://www.gunsmodify.com/news/detail-id-55.html