GI-1040 is a high tear strength, tin-catalyzed RTV-2 silicone rubber, which was designed for casting polyurethane foam parts. GI-1040 has a Shore A Hardness of 40, giving it the ability to resist distortion due to the expansion of the foam. GI-1040 is not sensitive to inhibition, meaning it will cure at room temperature over virtually any surface. It is easy to mix and de- air, and will cure with only a slight degree of shrinkage. The speed at which the rubber hardens can be accelerated with special activators. GI-1040 is also excellent for casting solid urethanes, polyesters and epoxies where a free standing mold that can maintain a straight edge is required.