Magic Bond seals leaks and repairs gouges in steel, aluminum, wood, fiberglass, concrete, and ceramics. Kneaded by hand, 2-part system becomes single color when mixed thoroughly. It hardens in 30-40 min to rock-hard finish that withstands sanding, painting, machining, tapping, drilling, and up to 250°F. Waterproof epoxy putty comes in 4 oz sticks.