Fan spacers position fan closer to radiator or fan shroud and away from pulleys. 1.5"-3" spacers are uniquely designed allowing spacer to remain bolted to water pump while changing fans. Aluminum spacers include reducer bushing, four Allen bolts to secure spacer to water pump and four hex bolts with washers to secure fan to spacer. Spacers work with 1-3/4" bolt circle flanges only. Note: ALL30180 and ALL30182 include one set of four Allen bolts only.