I love this product! You should see my cupboards with all the "Urine Remover / Stain Lifter" and all different brands natural or not I've tried. Most of the time those only worked on fresh or semi-fresh stains. Anything set in I could lighten but you'd still see it. (We have 3 dogs and 3 cats)
First day I went at the oldest stains in my house, along with some fresh ones on our brand new purple mattress (unfortunately, the mattress cover is WHITE) but low and behold 2 applications on the mattress and it was gone while the carpet old stains took a few days with a couple applications and they've been there for years!
I was hesitant because of the price but I'm sold now. I don't want any other cleaner for my household!