This is a built up discontinued magpul ssg. Almost all of the internals have been switched out for upgraded parts. Internals: Retro arms cnc Red gearbox shell Shs 12:1 gearset shortstroked 3 teeth Lonex ported cylinder Matrix silent cylinder head Lonex silent piston head Kratos piston Guarder tappet plate Shs delayer chip Gate titan advanced Angel custom trigger Shimmed amd lubed Asg 30k motor MAXX ME pro and rhop set up by Dan Blomquist 270 mm tight bore barrel Externals: G&p MOE body pistol grip and hand guard Pts Eps in Fde Exps repro and g33 combo Storm suppressor Magpul Moe rvg