a heat - recoverable article such as a heat - shrinkable wrap - around sleeve is provided with at least one auxiliary conduit so as to facilitate its application to the installation and repair of break - out joints from main - line cables , especially power and telephone cables . the auxiliary conduit is formed by bonding together appropriate regions of the internal principal surface of the article , coupled if necessary with a cutting step . bonding is preferably achieved by use of a cross - linking material such as a peroxide .