Tipped over, this silicone cap won’t leak. It even allows for drinking while lying down. The cap is completely closed while not in use, but biting down lightly on the cap opens it and allows liquid to flow out a little at a time. Made with silicone rubber that is soft yet resilient, the original non-spill system keeps the contents of a bottle or cup from spilling. Because suction is not required for drinking, there is no risk of unexpected choking. Easily attached to drinking vessels, this cap is highly durable and easy to use. Just turn it inside out, and every nook and cranny can be washed with ease. It can also be boiled to disinfect it.