Infinity Bond Tough Guy hot Melt glue sticks are the 'stick-to-anything' glue sticks. If every other hot melt has failed, it's time to try Tough Guy. This super high-performance formulation offers a strong, flexible bond to almost any substrate. Tough Guy offers the strongest all-around bond to the widest range of substrates. It also offers excellent temperature resistance at both hot and cold ranges and a flexible bond for extra staying power. Because of the high-temperature formulation, we recommend applying Tough Guy with a hot melt glue gun with at least 150 Watts of power. This will ensure it is being applied at the optimal performance and does not damage your gun.