Abstract: The invention involves a heat-shrinkable connection comprising a longitudinal channel and a cooperating element thickened at its end. The channel is composed of lateral leg parts which are dimensionally stable under the application of heat, and of at least one shrink region adaptable to the cooperating element in positively locking fashion under the application of heat. The shrink region in the connecting region thereby facilitates the joining of the connecting elements along the formed parts to be connected or along the longitudinal edges of an envelope.