A cap for detachably enclosing an upper open end of a hollow vertical disposable container with liquid therein employs a flat horizontal disc having first and second openings disposed in spaced apart positions therein. The first opening is a pin hole. The second opening is relatively large. The disc...http://www.google.com.au/patents/US5366109?utm_source=gb-gplus-sharePatent US5366109 - Removable cap for disposable containers of liquid
