I used 5 cans of flexseal on the roof of my 12 foot camper. This was over a three week period i paid 25 dollers a can. My camper roof still leaks.in my opinon it did not work. $ 125 dollers plus tax and my roof still leaks. And the hole or holes i cant even find.so its not cracks. Its not big holes. But holes so small i cant even find them and my camper has not moved out of my yard since summer of 2011. But still leaks. Y is this. The whole roof was cleaned scrubbed and rinsed before i started... james