Like a small showerhead which has a squeeze button. You squirt it at your buthole after a poo... Only for countries with warm water I guess!
It's routed in to your plumbing behind the loo.
Once you get used to using them then you feel really really dirty if you simply wipe with tissue... Even before I discovered them I would try to make sure I take a dump once a day, *before* I showered is at all possible.