350 DTS Hypercure 2K Primer Gray is a hypercure, high solids, high build 2K Acrylic Urethane Primer Filler/Surfacer/Sealer. This unique product provides optimal color holdout and can be sanded within 45-60 minutes, with minimal sand scratch swelling. Mixed with the optional DTS-Direct to Substrate Hardener, ADV350 is designed to be used on properly prepared steel, galvanized, aluminum, fiberglass and previously painted surfaces. NOTE: Plastic surfaces should be treated with 5 STAR ADVANTAGE #59007 Adhesion Promoter. ADV350 dries to a smooth low sheen finish, with built-in guide coat properties.