Abstract: A tab and slot closure system has a tab member, a slot member, and an anti-pop open device. The tab member has a tab element which has a first region and a second region. The first region includes a proximal edge, and the second region includes a distal edge. The tab element is attached to the substrate element along a line of attachment. The slot member has an inboard portion, an outboard portion, and a slot disposed between the inboard portion and the outboard portion. The anti-pop open device is disposed on either the tab member or the slot member and reduces the likelihood of the tab member unintentionally disengaging the slot member when the tab and slot closure system is fastened.