A closure structure for a two-compartment vial having an open neck at one end thereof with an annular rim encircling the neck at the free end thereof. The closure structure includes a stopper which extends into the neck and has a protruding portion of reduced diameter. The closure structure also includes...http://www.google.es/patents/US4258845?utm_source=gb-gplus-sharePatente US4258845 - Activator closure for two-compartment vial
