Apply: Tension Spring can be used in many occasions, such as production and assembly, experiment, research and development, maintenance,Home Repair, etc. Springs Specification:Wire Diameter: 0.7mm/0.027"; Outer Diameter: 7mm/0.27"(OD); Free Length: 30mm/1.18". Design: The Extended Spring design with double hook, which can be better fixed on the mechanical equipment to ensure the stable operation of the equipment. About this Springs:Made of highly elastic and fatigue-resistant nickel-plated spring steel material. It is wear-resistant, heat-resistant, corrosion-resistant, no deformation, and more durable for long-term use. Package Content: 50pcs x Extension springs with hook ends.