Dayton washers are suitable for holding assemblies that are subjected to excessive vibration, increased torque, heat or corrosion. These units provide added tension and friction which resist threaded nuts, fasteners or bolts from slipping, turning and loosening under mechanical load. They have a specially designed I.D. (internal diameter) that allows easy sliding and grip the shaft components for positive sealing; and are compatible with Dayton pedestal and impeller pumps.