Permatex Radiator Repair Kit repairs cracks up to 4 inches long and holes up to 9mm in diameter. It also seals small holes and weak seams in gas tanks without welding or tank removal. The repair resin is designed to harden within 8-10 minutes and cures in 30 minutes. Formulated to repair all plastic and metal radiator tanks, this complete kit contains everything required for making professional-quality repairs in just minutes with easy-to-follow instructions with photographs.