TCP CFL Spring Lamp, 150W Equivalent, Daylight White (5100K) MOGUL Base Spiral Light Bulb Please note this CFL has a MOGUL base (larger than standard base) Non Dimmable Lifetime: 9.1 years Uses 42 watts vs. 150 watt incandescent (with same light output) saving you $118 over life of the bulb Estimated Annual Energy Cost to Operate (based on 3 hrs/day): $5.06