Flat washers are used under a bolt or nut to provide a smooth bearing surface and to distribute the load over a wider area.

Fender washers have oversized dimensions like overall diameters and thicknesses.  Fender washers help cover oversized holes or can be used as a spacer.

Beveled Washers

Beveled washers are angled on their bearing surface to make up for surface imperfections in structural applications.  This condition is often seen in structural applications and buildings where the beams and channels are not parallel.  Beveled washers are to be used with A325 and A490 structural bolts.  

Timber Washers