Features:Mar-Glass(R) is a fiberglass-reinforced filler that features high strength and superb adhesion.Contains short strands of fiberglass and is ideal for use with fiberglass cloth when filling rust-outs, damaged fiberglass, deep dents, and small holes.Waterproof formula may be applied up to 3/4" thick.Finish with Marson Precision Glaze(R), Platinum Glaze(R) or Spot & Glazing Putty.Double the strength of standard body fillers.Includes 4 oz. White Cream Hardener.Marson 01160 1 Gallon Mar-Glass(R) with Hardener