Stabilized the rust and converted it to a primer.
My Cast Iron Urns were rusting out inside, so I bought this product to help save them.  I believe it has done exactly that.  After scraping the rust from the surface, then wire brushing, I applied this solution.  It  was magic the rust was<br />converted into a primer(?) or coating that turned mostly Black.  I then painted the urns with an oil paint for outdoor use.  The urns have been outside for 5 months now, in Humid Florida with no sign of rust.  This product is amazing.
Rating: 5 stars