The present invention provides a header for an implantable medical device that allows it to be used with either a unipolar lead or a bipolar lead. The set screw normally engaging a ring contact on a bipolar lead is stopped from extending far enough into an insulating layer on a unipolar lead to cause damage to the insulating layer. The use of the universal header of the present invention works to significantly reduce the number of different models of implantable medical devices that a manufacturer must have available.