Instant Power Hair & Grease Drain Opener, 1 Gallon Jug

I've been using this stuff for 5 years now, it comes in several sizes and is probably one of the best values out there overall - this is the largest size, which you can easily unclog 4-6 drains depending on how bad, or how often you clear them. I find that both bathroom and bathtub drains tend to get quite a bit of hair build up, and this is what this really excels at. Tips: 1.) If your drain hasn't been cleared in a while, add this to the drain before going to bed, then clear it by opening up the tap first thing in the morning. This clears the stubborn clogs. 2.) Get the largest one, it will give you the best value and last a long time. It also comes closed with a zip lock bag so you can make sure no drips or leaks get on anything while it is under the sink. 3.) I recommend running a couple of minutes of hot water into the sink prior to using this on that sink. It helps the liquid get down in deep into the sink. Overall this is the only drain clear I use now.

Very easy to use, you just pour it in the bathtub and let it work. It works fast. You'll need rubber gloves to protect your hands. And try to not breathe it in.