Rockford Spring Company is a custom spring manufacturer of compression springs, extension springs, and torsion springs. Rockford springs are available in wire sizes from 0.006 inches to 0.3 inches. Rockford uses standard music wire and other, more obscure materials. Rockford Spring Company received its certificate of registration under ISO-9001:2000, a world-wide recognized quality standard established by the International Organization for Standardization. Rockford Spring Company is a supplier to the following industries: automotive, electronics, agriculture, machine, tool, aerospace, medical, appliance, military and defense, construction and recreation. Rockford s Web site features educational articles about how springs function when used in various contraptions. The company is based in Rockford, Ill.