Purchased this product very recently to clean the zillion Rust spots & Rust marks on my boat. Just sprayed it on, left it to settle for about 30 seconds, then using a soft cloth just wiped it off.... and the rust spots/marks just came off without any effort. Also there were no visible scratches and/or damage to the fiberglass hull on my boat. Really impressed with this product !!!  Tried a couple of other products (sprays/powders) before I tried Starbrite, but as you can imagine they were pretty useless. Nice One Starbrite Rust Remover, will definitely be checking out the rest of your product range. This product should be freely available at more outlets.