Roma Plastilina is considered by many to be the world s finest modeling material. It is permanently pliable. The soft is extremely pliable and is used for making large sculptures it is easily scraped from molds. The medium grade is generally used for portrait heads, busts, and figure work. Medium grade is easy to work with and is the most popular consistency. Medium-firm is ideal for making models of smaller subjects. The extra hard grade is used in making extremely detailed objects such as medallions.