Oxalic Acid (2 lbs) 99.6% Pure - Multipurpose Cleaner and Stain Remover for Wood | Metal | Stone | Concrete - Rust Remover - Wood Restorer - Deck Cleaner - (C2H2O4) - Durable Resealable Packaging.

Worked well as a brightening agent in a pump-up sprayer in preparation for restraining my older cedar fence.Prior to using this using my pump sprayer, I applied a 1:1 ratio of outdoor rated chlorine bleach to water, then after 15 min rinsed off with my power washer. Then applied the Oxalic acid using the instructions on the pkg. Fence looked great when done and ready for staining.

I'm cleaning up some iron stains on an outdoor tile porch that have been there for many years. The stains are from the feet of iron lounge chairs and are pretty deep. I tried hardware store lime/calcium/rust remover and it had no effect. I put Oxalic acid on the tile for about 10 minutes and voila - the iron stains are completely gone. I don't know how toxic this stuff is, so I used thick rubber gloves and was careful not to get any on me. I wiped up the excess rather than flush it into the lawn. It also lightened the grout, which was pretty dull.

I use this stuff on wood. Works great

Works well

I knew it was strong when i bought it, but be warned, it is REAL strong! We had 20-year-old rust stains on a bathtub and it not only removed the rust stain but it left it feeling like 100-grit sandpaper, so use carefully. Don't leave it on to long.

use this stuff mixed with water in a spray bottle to remove those brown boat hull stains

10 star product

Good packaging