Sealing insert for containers

Claim 1

AN INSERT OF FLEXIBLE MATERIAL FOR A CONTAINER NECK, SAID INSERT COMPRISING: A CYLINDRICAL BODY ADAPTED TO BE COMPLEMENTALLY RECEIVED WITHIN SAID NECK; A CONTINUOUS, OUTTURNED FLANGE AT THE NORMALLY UPPERMOST END OF THE BODY OVERLYING THE NECK WHEN THE BODY IS RECEIVED THEREIN, SAID BODY HAVING AN EXTERNALLY BEVELLED BAND THEREAROUND AT THE OPPOSITE END THEREOF, SAID BAND HAVING A LOWERMOST EXTREMITY DISPOSED IN RADIALLY INWARDLY SPACED RELATIONSHIP TO THE CIRCUMFERENTIAL PERIPHERY OF SAID BODY, AND A PAIR OF DIAMETRICALLY OPPOSED, ARCUATE FEATHEREDGES AT SAID EXTREMITY; AND A PAIR OF SPACED, ELONGATED, DIAMETRICALLY OPPOSED, TRANSVERSELY U-SHAPED LIPS EACH PROVIDED WITH A TRANSVERSELY ARCUATE BIGHT AND A PAIR OF SPACED, FLAT WINGS INTEGRAL WITH THE BIGHT, SAID LIPS EXTENDING DOWNWARDLY FROM SAID BAND BETWEEN SAID FEATHEREDGES, SAID BIGHTS BEING INTEGRAL WITH THE BAND AT SAID EXTREMITY, THEREBY DEFINING A LINE OF FLEXURE FOR EACH BIGHT RESPECTIVELY AT THE UNION OF THE BIGHT AND THE BAND WHEREBY, BY VIRTUE OF THE BEVELLED BAND, THE LINES CLEAR THE NECK WHEN THE BODY IS RECEIVED THEREWITHIN TO PERMIT FREE FLEXURE OF THE LIPS WITHOUT INTERFERENCE FROM THE NECK WHEN POSITIONED FOR NORMAL USE THEREIN, SAID WINGS EXTENDING INWARDLY FROM THE INNERMOST, CONCAVE SURFACES OF CORRESPONDING BIGHTS AND HAVING UPPERMOST ENDS SPACED FROM SAID FEATHEREDGES THEREBENEATH, EACH WING HAVING AN UPRIGHT EDGE EXTENDING DOWNWARDLY FROM SAID END THEREOF, THE UPRIGHT EDGES OF THE WINGS OF ONE OF THE LIPS BEING SPACED FROM THE UPRIGHT EDGES OF THE CORRESPONDING WINGS OF THE OTHER OF SAID LIPS.