The Straw Stopper is like the little clasp used to keep the liquid from floating out of the beverage bag in space. Instead of having to use your hands to open and close it each time you drink from the straw, you can bite into it so that it opens the straw, closing as you let go of it. It works like a cord stopper because the holes from the two stoppers and the straw holder would align once the two “buttons” that move the stoppers are pressed to open the straw. Springs push against both stoppers make, so the stoppers would press against each other to close the straw. The straw holder fits a straw that is approximately 8 mm in size, and it is supposed to be slipped on top of the straw. This requires some assembly of three pieces.