The Professor knows, great product
People laugh when I tell them this stuff works! Follow the directions, and it has worked just as advertised for me. My son called from college, and the bathtub and sink drains in the old house him and 3 others were renting was clogged bad. LL was out of town due to emergency, so we shipped some to them using Amazon Prime next day. They used it as advertised, clogg gone. (Told the LL about it, now he's using it lol)<br /><br />I use it every few months in our bathrooms and kitchen sink, and although an older home, draing working well, and no odors.  Also seems to have helped get rid of them pesky little fruit flies we seemed to have encountered every late summer.
Rating: 5 stars