Product Description Easy to use putty permanently seals small holes cracks, or split seams without draining or removing gas tank or radiator. Hardens like steel in 2-4 hours. Full cure in 12 hours. For repairing small leaks or cracks in fuel tanks and radiators. From the Manufacturer Easy to use putty permanently seals small holes cracks, or split seams without draining or removing gas tank or radiator. Hardens like steel in 2-4 hours. Full cure in 12 hours. For repairing small leaks or cracks in fuel tanks and radiators.