Bonds in 4 minutes cures in 4 hrs. J-B Weld KwikWeld is an easy-to-use, lightning-fast bonding agent that works great for hobbies, crafts, household repairs, plumbing even patching leaky gas tanks. When you need to fix something fast and dont have the time or patience to hold it in place for half an hour while the hardener sets up, or wait for it to cure overnight, theres J-B Weld KwikWeld. Withstands temperatures up to 300F. Size: 2 oz. Cancer and Reproductive Harm- www.P65Warnings.ca.gov.