This is the hardener for the KD3000 Series DTS Primer Surfacer/Sealer, mixed at a 1:4 ratio (1 part hardener to 4 parts primer). The KD3000 Series is a hybrid epoxy, two-component primer system, designed for use as a Direct to Substrate (DTS) high or medium build surfacer/sealer, available in 6 premixed colors that can be intermixed for a wide range of colors. KD3000 has excellent adhesion, corrosion resistance, productive dry times, and ease of sanding, with very low VOCs, no HAPS, and no isocyanates. It can be applied over existing OEM finishes, bare steel, aluminum, fiberglass, galvanized surfaces, and various plastics.