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Claim 1

A TWO-PIECE FLUID DISPENSING CLOSURE FOR A CONTAINER COMPRISING: A FIXED PART HAVING MEANS FOR FLUID SEALING ATTACHMENT TO SAID CONTAINER AND A MOVABLE PART OPERABLE WITH SAID FIXED PART TO OPEN DISPENSING AND CLOSED SEALING POSITIONS THEREWITH, SAID FIXED PART HAVING A VALVE SEAT, ATTACHMENT MEANS ADJACENT TO SAID VALVE SEAT FOR POSITIONING SAID MOVABLE PART IN OPERABLE ASSOCIATION THEREWITH, SAID VALVE SEAT BEING IN COMMUNICATION WITH THE INTERIOR OF SAID CONTAINER AND HAVING A VALVE OPENING, SAID MOVABLE PART HAVING A CLOSURE FLANGE POSITIONED ABOVE SAID VALVE OPENING AND A DISPENSING OPENING OFFSET FROM SAID VALVE OPENING, SAID CLOSURE FLANGE SNAPPABLE BETWEEN A FIRST STABLE POSITION OF SEALING CONTACT WITH SAID VALVE SEAT IN SAID CLOSED SEALING POSITION AND A SECOND STABLE POSITION IN SPACED RELATION TO SAID VALVE SEAT IN SAID OPEN DISPENSING POSITION, AND WHEREIN PERIPHERAL PORTIONS OF SAID CLOSURE FLANGE CONTACT SAID FIXED PART ATTACHMENT MEANS AND ARE HELD THEREBY IN FIXED LATERAL RELATION WITH SAID VALVE SEAT AND WHEREIN BUCKLE TYPE HINGE MEANS ARE EMPLOYED, SAID BUCKLE HINGE MEANS PERMITTING LONGITUDINAL MOVEMENT STRESS UPON SAID MOVABLE PART IN ALL POSITIONS THEREOF EXCEPT SAID STABLE CLOSED SEALING AND OPEN DISPENSING POSITIONS, SAID HINGE MEANS COMPRISES A SUBSTANTIALLY CONTINUOUS GROOVED PORTION WITHIN SAID CLOSURE FLANGE ADJACENT TO AND SURROUNDING SAID DISPENSING OPENING.