T4 CFL bulb is designed to perfectly illuminate home offices, hospitals, storage rooms and more with cool white light. Spiral bulb uses 40 watts of energy that's equivalent to a 150-watt incandescent light bulb. Bulb has a CRI of 82 and is capable of producing 2,600 lumens for 10,000 hours. At 4,100 Kelvin, this 120-volt bulb is nondimmable and features a medium base. Energy Star qualified and RoHS compliant.