The most common style of washer used to prevent nuts and bolts from backing out.
GalvanisedHot dipped galvanised steel has a very heavy coating of zinc for better corrosion resistance, making it suitable for outdoor use. Because of the thick plating, only galvanised nuts and washers will fit galvanised bolts. The coating typically has a rough, dull grey finish.
Zinc / Mild SteelA low carbon steel for general use. Zinc plating provides a moderate corrosion resistance suitable for indoors or otherwise dry conditions. Colour is either a blue-ish tint or yellow depending on the exact process utilised during manufacture.
304 Stainless Steel304 Stainless Steel composition is 18% chromium and 8% nickel. When working with 304 Stainless Steels, it is recommended that stainless tools are used. This avoids cross contamination of stainless by easily corroded metals.
316 Stainless Steel316 Stainless Steel has increased corrosion resistance due to the addition of 2% to 3% molybdenum. It is suitable for marine, chemical, petrochemical, manufacturing and transport use.