Flex Seal Black FSR20 Liquid Rubber Sealant & Coating 14 oz
Product Review (submitted on June 27, 2013):
I tried filling a decent sized crack in the bottom of my plastic boat. I put several thin coats on one at a time & let each coat cure completely. After about 1 1/2 weeks & before I put the boat in the water, the flex seal began to crack & chipped off. The area I was sealing had some flex to it, which is what caused the cracking. I assume if the area had no flex, the product would work. However, the product once cured, does NOT FLEX.