a method and apparatus are disclosed for preforming a heat - shrinkable member to a pre - selected configuration which may at least partially conform to a container to which the member is to be applied . the preformed member is subsequently applied to the container so that the member is retained in association therewith , such as for tamper - indication . the heat - shrinkable member is initially preformed by the use of a preforming mandrel which may be at least partially configured like the configuration of the container . after the member has been heat - shrunk on the preforming mandrel , it is positioned in association with the container , and thereafter heated so as to further conform the heat - shrinkable member to the configuration of the container . by this technique , hightly desirable control of the heat - shrinking process is achieved , thus assuring proper conformance of the heat - shrinkable member to its associated container . a further feature of the invention relates to final application of the preformed heat - shrinkable member by localized heating of the member , which desirably minimizes heating of the associated container and its contents .