Raymond® ISO Series Die Springs (ISO 10243 and NAAMS) are offered in four duty ranges: light, medium, heavy, and extra heavy. ISO Die Springs are ideal for sheet metal forming or other press tool applications that need a spring force applied or other applications that need to store and release energy. Die Springs can apply a higher force per inch of compression or deflection compared to traditional Compression Springs. Utilizing Raymond® Die Springs enables high lifecycles, longer durability, and longer up-time between maintenance teardowns.