Dynatron Fiberglass Mat helps repair defects such as holes, cracks and tears in fiberglass, metal, wood, aluminum and masonry. Our fiberglass mat will not rust or rot. Use with Bondo Fiberglass Repair Resin for hundreds of repairs to tubs, showers, cars, boats, trucks, RVs and more. Product Features:Fiberglass mat reinforces repairsMat adds strengthEasy-to-cut mat allows for custom shapes and sizesPliable cloth conforms to curvesDesigned to work with fiberglass resin