Two piece hinged closure

In combination with a container having a mouth, a closure for said container, said combination comprising, a cap including a container closing portion and a skirt to be positioned adjacent to and over said mouth, a hinge connecting said skirt to said container closing portion, said container closing portion, skirt and hinge being molded as a single piece, a hinge abutment surface on said skirt positioned upon said mouth and along a sloped plane inclined with respect to a vertical axis of said mouth, said hinge including a flexible cam tab with a free edge engaged against said inclined abutment surface, a pair of opposed hinge straps located on either side of said cam tab, whereby movement of said cap between a first closed position on said mouth and a second open position causes said hinge straps to stretch and said cam tab to move along said hinge abutment surface and to snap over center to retain said cap in said open position, said cam tab resting against and generally parallel with respect to said abutment surface in said open position.