Flat washer provides a bearing surface for fastener load distribution or acts as a spacer
Steel is often used in applications where strength is the primary consideration
Plain surface has no finish
Meets ASME B18.22.1 specifications
Black sticky stuff on the item is just oil added to keep them from rusting
Description
The steel flat washer has a plain finish and meets American Society of Mechanical Engineers ASME B18.22.1 specifications. The flat washer provides a bearing surface for fastener load distribution or is used as a spacer between components. Steel is often used in applications where strength is the primary consideration.
Washers distribute the load of a fastener across a surface and can also be used as spacers, springs, shims, or locking devices. Several different washer styles fit a variety of application and installation requirements. The most common style is a flat washer. More specialized washers provide additional benefits. A cup washer, for example, helps protect fasteners from electrical currents, while a lock washer offers additional security in an assembled workpiece.