a high - temperature patch plug for one or more connection lines , especially for connecting electric supply and / or signal lines to heating elements and / or thermocouples or temperature sensors . the patch plug has one or more poles each with a contact element connected to an inner conductor of a connection line , and with a one - piece , insulating housing , which surrounds an interior , in which at least the at least one contact element is accommodated at least partially . the housing has at least one insertion opening on the side facing away from the plugging side and a passage opening , which is connected to the insertion opening via the interior of housing for each pole on the side facing the plugging side . the contact element is locked in the housing for each pole at a locking step arranged in the interior of the housing such that a motion of the contact element against the plugging direction is limited by the locking , wherein said locking step is formed by an irreversible deformation of housing .