Convert your existing fluorescent fixture to LED technology with the Feit Electric T4819/LEDIF/41K 4 ft T8/T12 LED lamps. This 4100K cool white light is non-dimmable. It produces a similar light output (1650 Lumens) and uses 19 W of electricity. Get instant on to full brightness with relatively cool running performance. Feit Electric shatterproof T8/T12 bulbs have an average life of 50,000 hrs/45.7 years are RoHS compliant and are 100% mercury-free.