greater extent comparatively as a result of the phenomenon of the controllable or differential stretching feature of the invention the overall film thickness is more widely distributed within the resulting blister structure e g the blister base film thickness is more similar to the starting film thickness as compared to the side film thickness which accommodates more of the stretch this is in contrast to conventionally formed blisters wherein the film thickness is distributed in diminishing thickness toward the center of the blister base thereby increasing the likelihood of excessively thinned areas or causing ruptures the stretching of the film from around the edges of the blister rather than from the base in initial movement of the pin is accomplished by controlling the friction between the peripheral area of the end face of the pin and the laminated film accordingly the pin structure i e topography or molding of the pin face the configuration of the pin body the materials used for the pin and combinations thereof can be adapted or modified to control or increase the friction when contacting the laminated film surface the topography or molding of the pin face comprises an indicia to be embossed complementary to that of the platen when engaged therewith the pin face can further comprise a surface periphery which is substantially flat alternatively the face of the pin with the indicia can be configured to be slightly concave shape whereby a peripheral edge is provided which increases the friction of the pin when contacting the laminated film the configuration of the pin body adjacent to the pin face can be adapted to modify the friction as well in one embodiment the pin body configuration can be adapted.