Torsion springs and extension springs operate differently. Torsion springs use a twisting force (called torque), whereas extension springs stretch (or extend) to lift the garage door.

Extension Springs from Lee Spring provide a solution to problems of linking components in a way that absorbs and stores energy, as well as creating resistance to a pulling force. They are pre-loaded ...

This extension cord has sturdy feel and soft touch right out of the package. Its 12-gauge size and 50-foot length deliver a nice balance of power and mobility, and the lighted end lets you know it ...