An extension spring system uses springs that stretch and retract to close and open your garage door. To learn more about how an extension spring system works, click here. They are installed along your horizontal track. In an extension spring system, there are two different types of springs: double loop and shackle clip.

Good: Double loop springs use the coils of the spring to create a 2-layer loop at each end that connect to the eye hook and pulley.

Best: The shackle clip spring doesn’t use part of the coil because the clip is bent around the end of the spring. It is not as susceptible to wear and tear as the double loop spring, which ultimately break at the end because of the design.