If you are looking for customized and non-standard China supplier jockey pulley from one of the famous China derailleur gears manufacturers and factory, please feel free to contact CFSM.Material: ZG55/ZG35SiMnWeight: 2.89tManufacture process: Sand casting +MachiningDescription: To support belting leather on the cement mill and belting leather support cylinder then the big gear ring push the cylinder to rotatesFunction: A jockey wheel is a retractable adjustable-height wheel used on the front of trailers with either a single axle (two running wheels) or more close-coupled axles at or near the centre of gravity whereby without additional support, the trailer would not remain 'level'.