This light base is for use with RP-19200 series lenses and most 3.75-inches two bulb sealed lenses. It has a chrome plated base with a 2-screw mounting and a rubber sealed 2-pin connector. Use with RP-19200 series lenses & most 3.75-inches two bulb sealed lenses Chrome plated base Rubber sealed 2-pin connector 2-screw mounting MODEL NO - RP-12611