Power springs are made of rectangular area material, Power springs are twisted level, and have either extraordinary holding openings or curves on the two finishes. As the length-to-thickness proportion (L/t) builds, the winding space between loops increments quickly. To lessen the space required and keep up a sensible measure of redirection (turns), power springs are held in some sort... https://www.neximalloys.com/power-spring-manufacturers-exporters-suppliers-stockists.html