Our Bondo Fiberglass Repair Kit lets users do it themselves for easy, cost-effective, shop quality auto body repair. The repair kit includes cloth, resin and hardener, along with a mixing tray, mixing stick and a spreader for straightforward application over cracks and metal rust-outs. The resin bonds to metals and plastics and hardens to a sandable surface in less than two hours. The seal created by the polyester resin material is permanent, waterproof and will not shrink. It can even be used as a sealer for damaged wood and on marine applications.