TO PERFORM PROPERLY IN USE, a coating must possess the proper amount of flexibility and toughness to withstand cracking when subjected to stresses produced by shrinking or swelling, forming, mechanical abuse, and weathering. Flexibility is the ability of a material to be bent or flexed without cracking or undergoing other failure. Toughness is the strength and resilience of a material; it is the material's ability to withstand great strain imposed in a short time period without tearing, breaking, or rupture.