OSPHO Metal Treatment / Rust Inhibitor Treatment / Primer, Quart.

OSPHO Metal Treatment / Rust Inhibitor Treatment / Primer, Quart. OSPHO is a rust inhibiting coating that provides a sound base for subsequent primers and paints. When applied to rusted surfaces, OSPHO causes rust (iron oxide) to chemically change to iron phosphate - an inert, hard, black substance. Where rusted metal is exceedingly heavy, two coats of OSPHO may be necessary. The OSPHO dries to a