Weston Industries offers Closed Wound Extension Spring. Weston Industries supplies a wide range of springs like compression springs, extension springs, conical springs and also wire form components for use in various industrial applications. The Closed Wound Extension Spring is used to absorb and store energy by providing resistance to a pulling force and also extends as a result of the pulling force. The Closed Wound Extension Spring uses various types of ends to attach the extension spring to the source of the force.