Tubular cable adapter for joining or terminating a medium-voltage cable

A cold-shrinkable element for joining or terminating electric cables, the element comprising a set of insulating or conductive layers, an outer protective sleeve, and a support element enabling said set of layers to be maintained in a radially-expanded state, the support element being suitable for being withdrawn from said assembly so as to allow the layers to shrink onto the cable or cables. According to the invention, the element comprises a metallized sheet disposed between said set of layers and said protective sleeve, together with a moisture-absorbing swelling layer disposed between said set of layers and said metallized sheet.