Abstract: By providing an intermediate substrate (30), which has been treated with an adhesion promoter (31), as an integral component of the sealing system of a plastic product or an elongated, slit, thermoplastic or elastomeric tube (23), a cohesive bond is achieved in the sealing system which virtually eliminates opening of the plastic product or thermoplastic or elastomeric tube (23) without degradation of the material itself. The adhesion promoting agent (31) may comprise of a treatment for the intermediate substrate (30) or may comprise of a separate layer affixed to the substrate (30). As a result, a highly effective, easily employed, self-sealing closure/surement system for securely affixing two surfaces (21, 22) to each other is attained.