My initial purpose for trying (and buying) this product was to remove rust from a cast iron table saw top. I discovered that there was a better (and less expensive) method for doing that ... it's called mineral spirits and ScotchBrite pads. However, after that removal, there is still a need to prevent rust from reforming on the surface and that is where Boeshield T-9 has done an excellent job for me. And not only on the cast iron table saw top, but on other bare metal items as well, especially on garden tools. I plan on having rust-free metal surfaces from here on out, including cast iron and all other exposed bare-metal tools and parts as well. I've only had the product for a month, so I cannot comment on long-term performance, but I'm guessing that it will do really well!