Tempo's Zinc Phosphate Primer is a non-sandable, chromate free primer that fuses to aluminum, steel and iron. It provides excellent corrosion protection. May be left un-coated , or top coated with Aircraft Enamel, Propeller Epoxy Coating or Aircraft Lacquer. Meets the corrosion performance requirements for TT-P-1757. Tack free in 10 minutes. Fully dry in 48 hours. Recoat after 30 minutes.