Abstract: A thin walled, flexible container and a closure is provided for sealing an open mouth of the container. The container is a blow molded, thin walled and flexible bottle. The container includes a cylindrical neck having a multi-lead thread construction on an outer surface. The closure includes a substantially cylindrical cap shell having an end panel that extends into a downwardly depending cylindrical side wall forming a skirt portion. A generally cylindrical gasket is adhered to the end panel of the closure. The gasket includes a generally flat annular surface that cooperates with the sealing surface of the container neck to form a seal and provide support to the container rim for resisting mouth-distorting forces.