This is the 1/2" NPT fitting nipple that is required to install your coolant line to your intake manifold.
Replaces steel GM part # 25518895
This is an aluminum Blue anodized fitting.
Replaces your old used steel unit that is 30 years old.
Saves weight & gives that nice clean look to your old or new ported intake manifold.
Whether you are restoring or simply lost your fitting this is an excellent replacement.
Can be stripped or painted color.