Ecoxall Oxalic Acid Fine Powder, 99% Pure, 1 lb (16 oz), Pack of 1

This cleaned that toilet in 20 minutes, I didn't have much time left as I was getting off work, so I had to rush in see just how well this,was going to work? And it cleaned so well , in such a short amount of time added in warm water to the mixture and made a paste and blotted it on to the stain.

The stuff works breaks up and removes rust

I used the Oxalic acid to remove stains from my hardwood floor after sanding out the top layer of stain. It helped lighten and remove many of the stains but did not work quite as advertised. I would buy this product again and it worked well, but not perfectly. Be careful when using as it is clearly an acid.

Decent price. Arrived timely. Did what it's supposed to.

Great product. Removed all water rust stains on the house from the sprinkler system. Used 1 cup in a gallon of water. Used a paint roller to apply. Let it sit for 15 minutes, scrubbed just a little bit on spots that still had rust. Then rinsed with clean water and all rust was gone.

Worked amazingly well!

Deck prep before staining. 😚 You'll need to use a stripper first, of course to remove any old stain.

Having a bunch of fun using this to remove rust from old tools. The quality seems normal. By which I mean I don’t have an analysis protocol to say for sure how perfectly it is what it says, but it looks & behaves differently from malic & citric acid. The crystals seem to be uniformly sized, a bit smaller than kosher salt flakes. When I forget to wear gloves, the back side of my fingernails stains brown and I have indifferent luck scraping it clean. (the nail extending from the end, not the nail bed. I suspect it’s reacting to something on the nail even tho I use a nail brush at least daily.) If you want to de-rust iron, this is one workable option.