http://www.katyspring.com/ Full service extension, torsion, flat and compression springs manufacturing company. en-us http://www.katyspring.com/spring-height-calculation.htm Solid height is defined as the point where a compression spring can no longer move. http://www.katyspring.com/press/service-expands-to-include-heat-treating.html Katy Spring added heat treatment services to its growing breadth of procedures for a variety of metals.