FMC® 200 is a polysulfide rubber mold compound with high tear strength that cures overnight with negligible shrinkage. Molds made of FMC® 200 are very durable and will perform in production. The mix ratio is 100 parts of Part A to 12 parts of Part B by weight. FMC® 200 cures to a Shore hardness of 20 A.FMC® 200 is ideal for those applications that require capturing intricate detail from a variety of model surfaces. Unlike polyurethanes, FMC® 200 is not sensitive to moisture and can be poured directly over wet plaster or water/sulfur based clays. Common applications include molds for foundry and pattern work, sculpture (lost wax process), casting various gypsum products and waxes.