replaces Ideal Horizons 41004, ME-4, MWE-6, RE-5, RE-8, SS-4, SSE-4, SSW-6, SSWE-6, SV-4, SV-6, SVE-4, SVE-6, Lancaster Pump 4-6, LUV-4E, Siemens LP4125, Sunlight LP4125, GPH330T5VH/4. The lamp is 16 watts, 330 mm in length, rated effective life 10,000 hrs., change once a year.