Was bored, tinkered with your model again. You should really take more time making these since I can within a span of ten minutes tweak it to what I consider to be better.
You added two layers to the flask and then used twosided, you don't need to do that, that's the whole purpose of the two sided option. This little tinkering takes 2 kb less than your model, because of less vertices. If you want to add volume you could just go with modulate and two sided. Dark colors usually works better with poison than light colors.