Bondo(R) Fiberglass Resin Liquid Hardener for use with Bondo(R) Fiberglass Resin. Used as part of a 2-part system for extremely strong and waterproof repairs Bondo(R) Fiberglass Resin Liquid Hardener for use with Bondo(R) Fiberglass Resin. Used as part of a 2-part system, the liquid hardener is mixed with fiberglass resin to create extremely strong, durable and waterproof repairs. Once mixed, the fiberglass resin will cure in 2 hours. Use this product for interior and exterior home repairs including tubs, showers, sinks, pools, hot tubs, boats, and more. Directions for Use Use hardener with Bondo(R) Fiberglass Resin. For small applications use 10 drops of hardener per ounce (2 tablespoons) of the resin. For larger applications, use half of the liquid hardener supplied, to half of the resin container. Mix thoroughly. Do not mix the entire container with liquid hardener as working time will be shortened. Do not add hardener directly to resin container.
