First (10) and second (12) coupling parts interlink and each hold a light-conductive element. One part is flexibly pre-stressed so that light-conductive elements are pressed onto each other with their facing surfaces if the coupling parts interlink so as t...

The cable form (10 ) is surrounded by a removable protection sleeve, which is formed by a shrinkable plastic tube (26). The diameter of the tube is bigger than the diameter of the cable form and the tube ends are shrunk on the cable form.