Upgrade your existing fluorescent fixture to LED technology with the Feit Electric PL18AB/H/CCT/LED dual-mode bulbs. Designed with a 4-pin base, these horizontal lamps easily replace existing downlight fluorescents, while providing longer lasting and more energy-efficient light. Use the switch on the bulb to choose between 2700K Soft White, 3500K Neutral White and 4000K Cool White color temperatures. Versatile installation allows both plug and play replacement or operation without a ballast after basic rewiring of the fixture.