A replaceable automobile headlight lamp unit and headlight utilizing same wherein the unit's electric lamp (e.g., tungsten halogen) is securedly retained within a clamp member including an insulative base and a pair of spaced-apart retaining clips for grasping the lamp's press-sealed end portion. The base includes a curvilinear surface which mates with a surface having a similar configuration located within an insulative holder which also forms part of the invention. A pair of spaced contacts located within the holder pass through apertures within the base and are connected (e.g., welded) to the retention clips. A ball-joint arrangement is thus provided to enable facile alignment of the electric lamp relative to the holder prior to final securement between the holder and base components.