Abstract: A plastic bottle cap for use in sealing bottles, the cap having a first annular sealing flange engaging the internal wall surface of the bottle and a second annular sealing flange engaging the top surface of the bottle neck. The second flange is constructed with a flexible tip which flexes relative to the remaining portion of the second flange as it is engaged by the top of the bottle neck to produce a flapper type seal. The cap further includes a tamper-proof ring at its bottom end which is automatically torn away as the cap is unthreaded from the bottle.

Abstract: A tamper-proof container closure cap is provided with a self-removing ring which breaks away from the cap in a strip as the cap is twisted open. Specifically, the cap is provided with a pawled ring which is split, frangibly attached to the cap adjacent each end, and free of engagement with the cap for a substantial distance in the direction opposing cap twist off. This structure effects removal of the ring from both the cap and the container as the cap is twisted off.

Abstract: An overcap for receipt on a jar in surrounding relation to a threaded closure cap of the jar and which when mounted prevents tampering with the closure cap and unauthorized entry into the jar interior. The overcap includes an upper surface overlying the closure cap and a skirt depending circumferentially therefrom. The skirt is radially spaced from the closure cap substantially along its length so that the overcap is free for rotational movement relative to the closure cap and cannot be frictionally coupled to the closure cap to effect removal of the latter. The overcap is provided with a pull tab defined by lines of weakness in the upper surface and skirt so that a pulling force on the tab will fracture the overcap from the closure cap and permit authorized access to the cap and opening of the jar.