Does what it claims!
I had a stack of cotton T-shirts that had become brownish over the past 5 years.  I was about to donate them to a rag drive, but I remembered an old product that touted "active enzymes".  I couldn't find any - probably because I remember that the sewer department decided that these enzymes were eating away at the seals on some sewer pipes.<br />I still wanted to try, so I ordered this stuff.  I soaked the T-shirts for four hours in one cup of Biz and about three gallons of water.  The water turned yellow!  I couldn't wait!  I washed them normally then, and the result was spectacular!  They were white again.  Not brand-new white, but white nonetheless.<br />I've since used Biz on ring-around-the-collar white shirts, other delicate underthings and grimy old kitchen towels with similar results.  This is a winner.<br />OBTW: Pay attention to the directions on the box.  This stuff will do a job on your unprotected hands.  And, if you don't use it often, the effect on sewer pipe seals is minimal.
Rating: 5 stars