Duda Energy 1 Quart / 950ml 85% Food Grade Phosphoric Acid Rust Remover Clean Etch Metal

You put copper in a 20% solution and it turns bright, shiny, and smoousth. Better than it was, new.I've used it on iron rust too as preparation for repainting an old rusty outdoor chair. The rust was too thick to make the steel shiny, but it served the purpose. I'm sure it would work with many other metals.Prior to the invention of carbonation for soda, around 1920's they'd put a tiny drop of it in a soft drink. Its nice enough, though you can see why carbonation has replaced it.It is a real acid so treat it like one! You should dilute this stuff before using.OTOH, if you get some on your skin, you have time to run to the sink and wash it off before you get burned. Safer than, say, nitric acid. And strong acid is fun to try for all sorts of uses in the garage! Do not use w/o adult supervision.

Works. Turned my rust into black beauty

A quart goes a long way. Direct competitor would be General Hydroponics pH Down. MSDS sheet of that product I found from 2021 stated it was 10-17% phosphoric acid. You can make gallons of that yourself with this 85% food grade phosphoric for $23. Or you can buy a quart from GH already made for $15. Up to you but educate yourself on how to dilute acid, how to handle acid, and wear PPE if going this route.

Work ass intended

Product as described . Shipping next day . Well packaged . 5 Stars

I figured phosphoric acid might be a little safer to work with than some other acids, and I think it might have worked, with some hydrogen peroxide, but I've decided to go the stronger acid route.

Un buen producto

Gets the job done if you know what you're doing