infolded gusset may serve simply as a hermetic sealing web adapted to be ruptured for discharge of contents from the bag after opening of the bag it is adapted to be reclosed by securing the resilient separable fastener profiles together application_number US 81345077 A description on reference to fig1 one form of one piece extruded plastic bag 20 embodying features of the invention is depicted comprising a pouch body 21 having coextensive opposite side wall panels 22 integrally connected with upper mouth end portions 23 of the side wall panels 22 is an inturned security closure gusset 24 having upper end portions 25 which are integrally joined with the upper mouth end portions 23 of the side wall panels along integral fold junctures 27 the gusset wall portions 25 and the side panel portions 23 are of adequate width to provide double thickness flanges 28 at each side of the mouth of the bag and adapted for manipulation to open the bag mouth when desired formed integrally with the bag extrusion and in this instance integrally on the confronting surfaces of the walls of the gusset 24 at the lower sides of the flange portions 25 are separable fastener means comprising complementary resilient zipper type fastener profiles comprising a male profile 29 on one side and a female profile 30 on the other side the profiles.