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

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

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

Highly Corrosion-Resistant Black-Oxide 316 Stainless Steel—A finished appearance with the rust resistance of 316 stainless steel. Even if the coating wears off, these screws still hold up in environments with moisture, salt water, and most chemicals.

High-Strength 17-4 PH Stainless Steel—Nearly double the strength of 18-8 and 316 stainless steel. These screws won't rust in wet and outdoor environments, but they can't handle harsh chemicals and salt water as well as 316 stainless steel.

Highly Corrosion-Resistant High-Strength Bumax 88 Stainless Steel—Comparable in strength to Grade 5 steel and as corrosion resistant as 316 stainless steel. These screws are commonly used in demanding applications, such as marine environments and chemical processing.

Seize-Resistant Nitronic 60 Stainless Steel—A naturally slippery surface keeps these screws from sticking or binding as you install them. They're often used in particle-free environments, such as clean rooms, where an added coating or lubricant could contaminate your space. They also stand up to salt water and mild chemicals, such as cleaners and degreasers.