AK metal gear and piston
M4 metal HOP UP
M4CQB rear sight
safety
piston
M4RIS back sight
M4 CQB outside barrel(aluminum)
M4 CQB outside barrel lengthening(aluminum)
M4 CQB outside barrel + lengthening barrel (aluminum)
M4A1 outside barrel(aluminum )
M16A3 outside barrel(sy009)
M4 front sight