a resealable can end is provided including a neck and a cooperating cap member which can be sealed onto and removed from the neck , and is capable of containing product under pressure or vacuum if desired . this end may be added , by convention seaming methods , such as roll seaming or by appropriate adhesive , to a container body , or may be formed integrally with container bodies . the venting feature of the end will achieve a controlled release of differential internal - to - ambient pressure upon initial opening of the cap , and may also provide resealed containment of partial contents retained in the container , although the contents will no longer be under pressure or vacuum , as the case may be . the end may be applied to , or incorporated in , containers made of various material , such as aluminum , coated steel , or selected plastics .