Worked like a charm! I had a bad hair only clog and I poured almost half a bottle because this bottle is not very big and waited 6 hrs and poured hot water in sink. Only issue is I wish I would have bought it sooner. The longer it sits the better it works.
P.s. my husband bought drain-o and tried the hot water and baking soda thing...didnt Work for my hair clog.

I had a bathtub that drained at a snail's pace and would fill up quickly each time I showered. I tried everything out there to clear the drain and NOTHING worked; wasted so much $$$. Found this product on Amazon and followed directions exactly; I even wore protective gloves and glasses because this stuff is no joke, lol. I let it sit overnight as suggested. The next day, it was like I had a brand new drain because my tub was finally draining!! Wow. Highly, highly recommend!!!

Our house has 3 girls with long hair showering daily, so the shower drain gets clogged a few times a year, despite our best efforts to keep the hair out of the drain. This is the only thing that actually works. This isn't available in the local hardware store anymore, so the last time we had a clog, I bought Drain-O. Used the whole bottle and it didn't help the clog at all. I ordered this and it worked like a charm, as always. I won't bother wasting time with anything else again.

We had a quickly and rapidly worsening slow drain in our bathroom tub. Tired of using other brands that didn't seem to work very effectively and cost more money, I tried this based on Amazon reviews. My wife and daughter both have long hair, so tub drain slowness is not new, but we have yet to find a product that does what we want it to do.

On the bottle, it says it needs at least 1 hour, but that it is recommended to let it sit overnight. This is the first drain cleaner that has ever had that on the bottle. Because there was no need to use the shower, I left it in over night and then flushed hot water for about 5 minutes.

I'm pleased to say that the drain is good as new! I can hear that the drain is completely open and water is freely flowing through it. What a wonderful, cheap product that does exactly what it's supposed to do! Would recommend to anyone, especially for this price point!

I did NOT measure the amount used (two cups, the recommended amount, seemed too little to me), so I poured approximately half the bottle in the drain. Since other brands recommend the entire bottle for maximum performance, I figured I'd try half the bottle and see how it did. Well, perhaps only 2 cups was all that I needed!

The next test is to see how long it lasts. So far with other products, results vary. I'll update this review when I need to use another application.

Simply the best. This stuff works time and time again. My wife has long hair and hence a good deal goes down the drain. Over time the water will slow them come to a halt. I pour roughly half the bottle in (more then recommended) and in 30 minutes to an hour the drain is running like new. I can't imagine living without this stuff! I always keep an extra bottle in the house. Saves me a trip to the major home center to grab when things go wrong. Have used this in both sinks and tubs. Just try to aim directly for the drain opening. If using in a bathroom sink try to remove the plug before pouring in so you can pout directly into the drain hole as it may discolor the chrome or other metal.