I had to dial the dispenser all the way to the third gram to get anything to come out, so it appears I got 13 g instead of 15. I'd return it, but then I'd be without the benebac for my cat, who currently needs it. It was also Benebac Plus instead of original Benebac. The Plus has some "prebiotics", which are to feed the bacteria and help them multiply/survive better. Sounds good, however, it must change the flavor some because my cat who loves regular Benebac (thinks it is a treat and runs for the bowl when he sees me pick up the dispenser) would not eat it until I smeared it on his muzzle so he had to lick it off.Oct 2012 I tried them again, and it was fine--full tube. And the cats got used to the taste and now like it fine--just squeeze it onto a plate and they lick it up. My cat has a food allergy and he had been having slight diarrhea for a month--two doses of this and he was fine (no more soooo stinky litter box).