Premium high build formulation is a polyester primer-surfacer which can be used on fiberglass, aluminum and properly prepared steel. Eliminator HB has excellent adhesion, very high fill and superior solvent resistance when properly cured. On fiberglass it replaces damaged gel coat. This tough and durable coating resists stone chipping and abrasion and will fill 36 grit grinder marks in 2 to 3 coats. Cured primer in non-shrinking and compatible all automotive topcoats and meets all VOC regulations. 1 gallon includes 4oz liquid hardener