1、Die springs are primarily used in die machinery. 2、Its inner diameter is half of outer diameter in general. 3、For die springs, yellow color represents that the load grade is extra light load. 4、Additionally, the heaviest load grade die springs are made in brown color. 5、Widely used in stamping dies, metal die-casting dies, plastic dies as well as other elastic motion precision machinery and equipment, automotive fields. Features:  Die springs are primarily used in die machinery. Its inner diameter is half of outer diameter in general. For die springs, yellow color represents that the load grade is extra light load. Additionally, the heaviest load grade die springs are made in brown color. Widely used in stamping dies, metal die-casting dies, plastic dies as well as other elastic motion precision machinery and equipment, automotive fields. Specification: Model (OD*Length): TF12*20mm, TF12*30mm, TF12*40mm, TF12*50mm, TF12*60mm, TF12*70mm, TF12*80mm (Optional) Material: 65MN Steel Color: Yellow Load Grade: Extra Light Load Outer Diameter: 12mm Inner Diameter: 6mm   Package list: 2 * Die Spring