EZ-Spray 45 sprays easily, using the EZ-Spray Junior Cartridge System, onto vertical surfaces for making molds and is good for making fast molds of large surface areas. After a suitable thickness is attained, EZ-Spray 45 cures overnight with negligible shrinkage to a durable mold rubber. Application of a support shell is achieved by spraying Smooth-On’s EZ-Spray Plastic over the rubber mold after it has fully cured. Once a support shell is applied, you may cast a variety of materials including wax, gypsum, urethane and epoxy resins, and concrete.