A light system comprising: a driver compartment assembly; a heat sink adapter housing fixed to the driver compartment assembly, the heat sink adapter housing defining a plurality of openings that are each internally threaded; a light engine adapted to be removably attached to the heat sink adapter housing, the light engine including: a baseplate; optics coupled to the baseplate; a retainer ring removably mounted to the baseplate, the retainer ring including a plurality of mounting regions circumferentially positioned thereabout, wherein the plurality of mounting regions each include a plurality of discrete openings spaced apart equally in an arcuate array, each of the plurality of mounting regions corresponding to a circumferential flange segment of the retainer ring, the circumferential flange segments of the retainer ring being separated by projections, the plurality of discrete openings being defined through the circumferential flange segments, respectively; and a lens having an outer flange disposed between the baseplate and the retainer ring, the lens at least partially surrounding the optics to enclose the optics on the baseplate; wherein the retainer ring is rotatable relative to the heat sink adapter housing in discrete increments via the plurality of discrete openings, the plurality of discrete openings of the plurality of mounting regions each respectively corresponding to one of the plurality of openings of the heat sink adapter housing, wherein the optics rotate with the retainer ring to change the light distribution illumination direction emitted by the optics. a driver compartment assembly; a heat sink adapter housing fixed to the driver compartment assembly, the heat sink adapter housing defining a plurality of openings that are each internally threaded; a light engine adapted to be removably attached to the heat sink adapter housing, the light engine including: a baseplate; optics coupled to the baseplate; a retainer ring removably mounted to the baseplate, the retainer ring including a plurality of mounting regions circumferentially positioned thereabout, wherein the plurality of mounting regions each include a plurality of discrete openings spaced apart equally in an arcuate array, each of the plurality of mounting regions corresponding to a circumferential flange segment of the retainer ring, the circumferential flange segments of the retainer ring being separated by projections, the plurality of discrete openings being defined through the circumferential flange segments, respectively; and a lens having an outer flange disposed between the baseplate and the retainer ring, the lens at least partially surrounding the optics to enclose the optics on the baseplate; wherein the retainer ring is rotatable relative to the heat sink adapter housing in discrete increments via the plurality of discrete openings, the plurality of discrete openings of the plurality of mounting regions each respectively corresponding to one of the plurality of openings of the heat sink adapter housing, wherein the optics rotate with the retainer ring to change the light distribution illumination direction emitted by the optics. a baseplate; optics coupled to the baseplate; a retainer ring removably mounted to the baseplate, the retainer ring including a plurality of mounting regions circumferentially positioned thereabout, wherein the plurality of mounting regions each include a plurality of discrete openings spaced apart equally in an arcuate array, each of the plurality of mounting regions corresponding to a circumferential flange segment of the retainer ring, the circumferential flange segments of the retainer ring being separated by projections, the plurality of discrete openings being defined through the circumferential flange segments, respectively; and a lens having an outer flange disposed between the baseplate and the retainer ring, the lens at least partially surrounding the optics to enclose the optics on the baseplate; wherein the retainer ring is rotatable relative to the heat sink adapter housing in discrete increments via the plurality of discrete openings, the plurality of discrete openings of the plurality of mounting regions each respectively corresponding to one of the plurality of openings of the heat sink adapter housing, wherein the optics rotate with the retainer ring to change the light distribution illumination direction emitted by the optics.