The wavy shape flexes like a spring to keep nuts and screws secure on slightly uneven surfaces. These washers add a small amount of tension to stop fasteners from backing out due to mild vibration. While they don't hold as well as other lock washers, they do grip slightly better than curved washers. They work best in electrical panels, light fixtures, and other light duty assemblies. Since these washers hold their shape when untightened, you can reuse them a handful of times without losing strength.

18-8 Stainless Steel—The choice for wet and outdoor environments, these washers won't rust when exposed to moisture. However, they can't hold up to the harsh chemicals that 316 stainless steel can.

Black-Oxide 18-8 Stainless Steel—Typically chosen for their appearance, these washers have a dark, matte coating to create a finished look. They won't rust in wet and outdoor environments, but can't hold up to harsh chemicals as well as 316 stainless steel.

Super-Corrosion-Resistant 316 Stainless Steel—Superior to 18-8 stainless steel, these washers won't degrade when exposed to harsh weather, salt water, and most chemicals.

Zinc-Plated Steel—A common choice for areas with occasional exposure to moisture.

Black-Oxide Steel—Typically chosen for their appearance, these washers have a dark, matte coating that creates a finished look. They offer minimal corrosion resistance, so they're best for dry environments.

Steel—Best for dry environments since moisture will cause these washers to rust.

Super-Corrosion-Resistant Phosphor Bronze—Stronger and more wear resistant than silicon bronze, but with the same excellent corrosion resistance. These washers won't rust or deteriorate when submerged in salt water, so they're a good fit for marine environments.

3 Wave—More points of contact than single-wave washers for a better grip.

DIN 128B—These washers have split ends that bite into your material surface for a tighter hold than other wave washers.