The colors and sizes of these springs follow ISO 10243 for metric die springs. Made of chrome-silicon steel, they have high tensile strength for reliable, long-lasting operation in repetitive applications, such as punching and stamping. All have closed and ground ends, which provide a flat mounting surface for even movement and distribution of loads.

Deflection is the distance the spring compresses, expressed as a percentage of its length.

As you squeeze a die spring, it gets harder to push. Spring rate is the amount of force required for every millimeter of compression. The higher the spring rate, the harder it is to compress the spring.