Extension Spring Heavy Duty Pulley 3" for doors up to 200lb

Garage Door 3" Heavy Duty Solid Rivet Pulley with 3/8" bore. Works for doors up to 200lbs. Life cycles 10,000 +/- (1 open, 1 close = 1 cycle). For extension spring doors. Do you need the clevis straps to make this pulley a set? You can get the compatible hardware kit for a set of 3" pulleys here. NOT COMPATIBLE WITH TORSION OR TORQUEMASTER SPRING SYSTEMS. Includes: 3" Diameter Heavy Duty Sheave Pulley Specifications: Heavy Duty 200lb Load 6 Solid Rivet 3/8" Bore Compatible with up to 1/8" diameter cables for Extension Spring Doors Take a look at this diagram to see the different spring types: When it comes to garage door extension spring systems, it's important to remember that two springs are required to lift the weight of the door. For example, if you have a 80lb garage door, you will need two 80lb extension springs to lift it. When looking to replace your garage door extension springs, it's important to check the item description for information on size, life cycle and other s