GARAGE DOOR SPRING – This torsion spring includes a stationary cone and a winding cone attached to opposite ends of the spring; these types of torsion springs provide lifting force for heavy garage doors FIND THE RIGHT SPRING – Choose the right spring for your project bases on spring dimensions, not door weight; see the product specifications in Prime-Line’s Torsion Spring Selection Guide to assure proper garage door spring replacement selection STRONG AND DURABLE – Constructed of steel and finished in black with a silver painted end, these are regular-duty torsion springs for garage door with an estimated lifetime rating of 10,000 cycles INSTALLATION – Right hand wind garage door springs are mounted to the left of center (as viewed from the inside the garage looking out); when dual spring installations are involved, it is important to replace both springs DIMENSIONS – The garage torsion spring has a 0.207 inch wire size x 1-3/4 inch inside diameter x 18 inch overall length; for further dimensional information, please see the line drawing