Many Leatherman tools include a combination metal file and saw.
The Leatherman metal file has fine cutting grooves on one side, and coarser ones on the other, with serrations on one edge to use as a saw. The file is made of hard steel so it can cut through soft steel, and softer metals. You can also use it to cut or smooth wood, and other soft materials. It will not work on glass, ceramics, or hardened steel: those materials will dull the file very quickly.
The metal file is usually about 75mm (3") long on the larger multi-tools.