A washer is a disk-shaped plate, made of metal or plastic which is used to distribute the load of a threaded fastener, such as a bolt or a nut. It is also used as a spacer, spring, wear pad, and locking device & to reduce vibration.
Bushes play a key role in guiding the wheelset. As system components they can also be used to transmit loads in the traction link and anti-roll system as well as in the driveline suspensions.