I was spraying a frame one day with Por 15 and a bug landed on the frame so I spayed another coat over the bug. Two weeks later while assembling the chassis I came across the bug. I scraped the bug off with a knife and his guts were still wet. That's how well that stuff seals moisture out and in. I've sprayed about 20 chassis with that stuff and people are always asking if it's powder coating. I can usually spray a frame and all of the suspension components with one quart. It goes a long way. If you spray it you need to wear a respirator. Nasty stuff if you get it in your lungs. I love it! (not to the point of being sexual)