one another are melted together the sealing fin 10 can be raised in the manner which is shown in fig2 after the triangular lug 15 has been detached from the side face 14 and has been raised to the position shown as can be seen from fig2 the cut line 6 appears on either side of the base line of the sealing fin 10 and extends inwardly up to a point on the top face or upper end face 11 of the packing container the cut line 6 is thus doubled around the apex 5 of the triangular lug and the two parts of the cut line which are present on either side of the apex 5 are arranged alongside one another the cut line 6 is covered along the inside of the packing material in a manner described earlier by the longitudinally oriented plastic film 7 which is sealed to the inside of the package in the region of the cut 6 a part of the strip 7 has been incorporated in the sealing fin 10 thus these parts of the plastic strip 7 are combined and are taken up between packing material layers in the fin 10 while the parts of the strip 7 which are situated 34 below 34 the cut line 6 rest against the inside of the top side 11 of the packing container and the triangular lug 15 as mentioned earlier the plastic strip.