Its called a lung.What u do is cut the bottom off a plastic bottle e.g 2litre.Then u tape a plastic bag 2 the bottom of it. place a piece of foil where the lid go's and add ur weed as u burn the weed pull the bag down-wards with causes a vacuum drawing in the smoke.Remove foil and put mouth over,and push the bag up-wards.Result smoke forced in 2 lungs.