Write on tools or other metal surfaces without worrying about the marks wearing off. These pens contain an acid solution that flows like ink and removes a thin layer of metal to create permanent black marks. For best results, apply to clean, dry surfaces to prevent the solution from spreading. When you’re done marking, let the solution dry completely.

Use these kits for everything from permanently marking materials to cleaning and finishing surfaces. They come with all you need to get started, including an engraver, four types of tips, and a tip holder. The engraver is more powerful than an electric option, so you can make the same markings in fewer passes and with less effort. A continuous dial lets you adjust the stroke to mark materials as soft as plastic and wood and as hard as metal. When swapping in another tip style, you must secure it in the engraver with the included tip holder. These engravers need lubrication to work properly.

A fine-point tip cuts lettering, numbering, and designs in a variety of metals and composites, such as aluminum, fiberglass, and titanium. Made of solid carbide, these end mills are harder, stronger, and more wear resistant than high-speed steel and cobalt steel for the longest life and best finish on hard material. Their extreme hardness means they are brittle, so a highly rigid setup, such as a CNC machine, is necessary to prevent the end mill from breaking. All are center cutting, allowing plunge cuts into a surface.