Denny - OSPHO is 75%, the reason it's pricey, and like any it will act as a converter IF you use it like a paint prep - still a rust remover if you soak the part in it, and when soaking it can be diluted with at least 3 parts water, then if you return the solution to a closed container it can last as long as you'll be cleaning parts wink .... if you want cheap it'll always be a very dilute solution - unless it's a brand name, which will never be cheap - the DX520 is 7-13%, even DX579 is only 30-40% ... also I've heard even PPG doesn't recommend using DX520 anymore big_eek

Bill


Moved over to the Passing Lane

"When we tug a single thing in nature we find it attached to the rest of the world" John Muir
"When we tug a single thing on an old truck, we find it falls off" me
Some TF series details & TF heater pics & Rust-a-holics Unanimous parking lot