DURA-BILT Heavy-Duty 3" Galvanized Steel Garage Pulley with Fork & Bolt EXTRA-QUIET OPERATION: 9-ball bearing with high-temperature lubrication grease for smoother movement EXTENDED LUBRICATION: lubrication groove inside pulley to disperse grease over an extended period of time STANDARD PULLEY SIZE: 3-inch diameter pulley is the standard DIY replacement for your old, noisy pulley SIMPLE DIY REPLACEMENT: easily replace old or worn garage pulleys for smoother door operation