1. It is designed to allow craftsmen to form smooth curves from flat sheets of metal. 2. Mainly used in car, motorcycle, aviation and racing car construction or restoration where sheet metal panels need to have compound curves formed. 3. The operator passes the sheet metal between the anvil wheel and the rolling wheel. This process stretches the material and causes it to become thinner. As the material stretches, it forms a convex surface over the anvil wheel. 4. This heavy duty steel fabricated machine has a large 710mm throat which allows a capacity of 1.2mm for mild steel