This extension spring is made of stainless steel 316 and has an outside diameter (OD) of 0.12 inch and a wire size of 0.018 inch. It is made of stainless steel 316 for greater resistance to corrosion than steel music wire or stainless steel 302. The spring ends are full twist loops for secure fastening. This spring has a load capacity of 1.08 pounds, and a maximum operating temperature of 570 degrees F (300 degrees C). The surface is passivated per ASTM A967 for enhanced corrosion resistance. This stainless steel 316 spring meets American Society for Testing and Materials (ASTM) standard A313 (chemical and physical only) for quality assurance.

Extension springs are open-coil spiral (helical) springs that offer resistance to a tension force, or load, applied along the axis of the spring. When a load is placed on an extension spring, making it longer, the spring pulls back against the load to return to its original length. These springs are used in a variety of applications, including automotive engines, major appliances, medical devices, electronics, and sensitive measuring instruments.