ps. Liquid Plumber contains caustic Lye, a very nasty chemcial that if injested is lethal, & if it so much as splashes on your skin will immediately burn it.
If is splashes in your eyes when trying to pump out the head & it backs up it will cause blindness. It doesn't even get rid of the clog. The only thing it succeeds in is eating away your pipes & seals.
As Stu said its eats anything rubber or plastic. I work as a building inspector, & you'd be amazed about how corrosive Lye is to metal waste pipes. Should be illegal.
I actually think it was invented by plumbers to give them work to do when the crap eats through your pipes. But in reality, plumbers will charge extra if they find lye in your drain, because it you auger pipes with Draino in there & it splashes up, it can cause serious injuries.
Kinda like the other guy a couple of days ago who posted that he uses muriatic acid to clean his boat's deck. Way overkill & bad for the environment, & the user.