A series of pre-opened resealable bags formed as a continuous web and received on a roll suitable for implementation in an automatic bagging machine are presented. The web of bags consist of top and bottom films thermally bonded together along the edges thereof. Transverse resealable zipper strips are interposed between the top and bottom films, with mating portions thereof respectively bonded to an associated films. A top film is provided with a filling slit, adapted for receiving product or materials therethrough. Appropriate seals and perforations are provided transverse to the web to allow the bags to be separated from each other and to allow for operator access to the resealable zipper strip. In another embodiment, the zipper strips are substituted or supplemented with plastic reinforcing strips to accommodate a punched hold for hanging display of the bag. A process for manufacturing such bags from a pair of webs received inserted zipper strips is also presented.