J-B Weld HighHeat is a two-part epoxy system that provides strong, lasting, heat-resistant repairs up to 550°F. Mixed at a ratio of 1:1, it forms a permanent bond that has a 4730 PSI strength and is chemical and fuel resistant. At room temperature, HighHeat sets in 1 hour and cures in 24 hours. HighHeat's cure time is accelerated by heat and can cure in 1 hour at 250°F.