the present disclosure relates to plastic or polymeric container with reclosable zippers which make the package child - resistant . in one typical embodiment , this is achieved by a zipper with a high internal opening force and a low external opening force , wherein three flanges are sealed to the bag walls , and one external flange is left unsealed . in order to encounter the low external opening force , the user must grab the unsealed external flange while applying an external opening force to the zipper .