Designed for use in various models of lawn and garden equipment, this part is not sold as part of a kit or assembly. It is made of metal, is gold in color, and is sold individually. This part may also be called a Flange Lock. This nut is designed to lock in place, preventing vibrations and other parts coming loose. This nut may be located in multiple locations on your machine, refer to your owners manual to determine if this is the correct part. You will need a wrench or socket set and a torque wrench to complete this repair. You should only torque the nut to the manufacturer recommendation, no tighter. You will need to replace this part when it is worn or damaged. While this part can wear through regular use, it is most commonly damaged through improper use of a wrench or socket. Customers describe this repair as Easy.