Spent $20.00 at Canadian tire to repair an outdoor fountain, 2ft by 8in by 10in, water reservoir. Sprayed as directed, let dry as instructed, sprayed several coats as recommended, used a whole can spraying inside and out, did not even slow the leak down, cannot believe it would work on a boat if it can not hold 2 gals of water, what a joke and a waste of money. I will be sure to let everyone I know how poor this product is, will never purchase this product again.