Use the drawing, not the nickname
Crimp and Screw Necks: The Early Buying Decision is best approached as a measurable packaging decision, not a visual preference. Terms such as FEA15, 15mm screw or 18mm screw are useful search filters but do not prove interchangeability. Review the complete neck drawing: bead or thread geometry, bore, finish height, sealing land and tolerances. Match it to the exact pump drawing and assembly method.
Treat assembly as a controlled process
Crimp systems need suitable jaws, crimp diameter and height settings; screw systems need defined application torque and resistance to loosening. In both cases the gasket, glass finish and fragrance formula influence sealing. Document the approved machine settings together with the component lot.
Validate after decoration
Coating or metallisation around the shoulder and neck can change assembly height or interfere with a collar. Mask critical interfaces and repeat physical fit, leakage, cap engagement and spray tests after decoration. A drawing review is necessary, but a filled physical test remains the final evidence.