HD-CRY-DO Heavy Duty Cleaner Clears Clogs and Melts Grease Professional Strength Crystal Drain Opener, 100% Lye, Black

works great second time buying this product

I had a severely clogged bathroom shower drain. I had to use a lot of this product but it finally unclogged the drain and saved me a plumber's bill

Bathroom drain a problem, this WORKS well

When compared its price with similar products on market(7, 8 times more expensive), I thought it was able to solve my kitchen drain problem once and for all. But after multiple times use, things are getting worse and worse. Today I have to call in a plumber to fix the completely blocked drain. Very disappointed!!!

I had a stubborn clogged drain. Ordinary liquid drain cleaners did nothing to clear it; neither did a 50 foot plumbing snake. So I bought this Roebic concentrated sodium hydroxide. I planned to drop a few teaspoons down the drain. Wearing no protective gear. Oops. I accidentally spilled a LOT MORE (quarter cup?) on the measuring spoon. And the drain. And the water in it. WHOOSH. YOWWWW -- as the geyser hit the back of my ungloved left hand. The world turned white. Worst pain I've ever felt, worse than getting hit by a car, worse than watching the 2016 election. The sodium hydroxide was boiling the fat under the skin. Fun fact 1: the "heat of solution" of sodium hydroxide is about 1000 calories per gram of NaOH. 600 calories turns a gram of water into steam, Right Now Only. Fun fact 2: A quarter cup of NaOH is more than 100 grams. Fun fact 3: Soap can be made with sodium hydroxide plus animal fat. I grabbed some lemon juice from the fridge, and poured that on my hand - over a different sink. Weak acid neutralises alkali - fizz instead of boiling. Followed by a few hours alternately drying and soaking my hand in a weak solution of salt and lemon juice. Followed by a couple of weeks of salve, absorbent medical pads, and Coban tape. An oversized cloth glove is better for holding pads in place over a hand than Coban. Two months later, the hand is painless, the loose skin is healed and not too ugly, and I could type the letters on the left side of this keyboard. And the drain stopped up again. Episode 2: I used the drain line cleanout port in the basement. I dressed "full moon suit" - a surplus cleanroom suit with an actual helmet and air hose! - and wore heavy gloves, and tall boots with the pants cuffs OVER the top of the boots. Newspaper covering all surfaces nearby. I /carefully/ and /slowly/ measured out spoonfuls of the recommended amount of Roebic into a small bowl (with a flat bottom so it wouldn't tip), then /slowly/ spooned that into the cleanout port. No eruption, very anticlimactic ... thank goodness. Now the drain runs fine, and we treat it often with weaker (and safer) drain cleaners. Roebic is the 900 pound gorilla of drain cleaners. You should treat it like the variety of gorilla with a flamethower and hand grenades. If you are very careful, Roebic will do an excellent job of clearing clogs that are resistant to everything else. Treat the whole bottle of concentrated firepower like belt of hand grenades in a bad war movie. My one bottle will probably last for life, and certainly will last until the plague ends, when it is safe to bring in a crew to dig up and replace the drain line. I hope the Roebic product is available for a long time, and that they have very good liability lawyers, and that all you other customers are more careful and responsible than I was. Skip episode one, start with episode two.