Transtar 1K Fast Prime, 1Gallon, Light Gray. Transtar’s 1K Fast Prime is a low VOC, excellent quality one-component primer surfacer with good filling and sanding characteristics. This product dries quickly and provides good topcoat holdout. It may be used under acrylic enamels, acrylic lacquers, alkyd enamels, urethane enamels, and basecoat/clearcoat systems. 1K Fast Prime provides excellent adhesion and good featheredging properties. Reducer Acetone. Mix Ratio 1:1/2-1, Suitable Surfaces: Degreased and sanded existing finishes; properly prepared steel, aluminum and galvanized steel; fiberglass; body filler. 6071