This is complete loading nozzle assembly. Parts included: nozzle, valve, spring and o-ring.
Compatible with APFG MCX GBB.
Compatible with MARKSMAN K1A GBB.
Compatible with MARUYAMA ISO556 GBB.
NOT compatible with APFG MPX GBB.
NOT compatible with APFG XM7 GBB.
Adjustable NPAS included.