These devices are used in conjunction with a router (not included) to create spiral turnings. If you're at all interested in it you probably know more about it than I do. This model is missing the crank and maybe a few other parts but the mechanism and pulley wheels are intact, it works. Maybe somebody needs it for parts? Make me an offer I can't refuse. This tool is being sold as surplus on behalf of a local communal workshop named MakerSpace. There are many other items for sale, check them out. We're located at 4476 Markham Street and all items must be viewed there, generally in the evenings.