There are 2 styles, square/large square shaped with different scale, choosing based on your needs. Made of quality stainless steel, anti-rust and corrosion resistance, long for time service. Pulling this metal gauge tool out of your pocket to measure metal is quicker and easier than using a tape measure. You can determine the thickness of the material before welding or processing and measure the most popular welding thickness quickly and accurately. The sheet thickness gauge is useful for checking metal sheet wire size before welding or working, and is also easy to read.