I'm not sure whether it's just my unit or not since other reviews have been positive, but from my experience, this one is just plain bad. It smells like wet clothes left in a pile of garbage and doesn't remotely come close to smelling like an actual fart; there's no sulfur smell that a fart should have. I have this ziplocked in it's own bag to seal the scent away from my other bottles. Just spend your money on something else.
Its exactly as it says in the title, the smell be as like a skunk and man you can enjoy that on some very fucked up days. even better then those egirl bathwaters you'll find on ebay.