Plain Flat Washer, 3 mm

Plain flat washers, as seen here, are distinguished by their simple, unadorned design, lacking any teeth, splits, or complex shapes found in other washer types like lock washers or spring washers. Their primary function is to distribute the load of a threaded fastener, such as a nut or bolt, evenly across a larger surface area of the material being joined. This widespread load distribution helps prevent damage to the material, especially softer ones like wood or plastic, by reducing concentrated stress points that could lead to indentations, crushing, or cracks under the pressure of a tightening fastener. Beyond load distribution, flat washers can also act as spacers, filling gaps between components or adjusting the depth of a fastener's penetration. They can also serve as a barrier, preventing galvanic corrosion when dissimilar metals are in contact, or even provide electrical insulation if made from non-conductive materials like nylon. Their versatility makes them indispensable in numerous applications across industries, including construction, automotive, manufacturing, and general household repairs, ensuring secure, stable, and durable connections in a wide range of assemblies.