ALZO 45W Joyous Light Full Spectrum CFL Light Bulb 5500K, 2800 Lumens, 120V, Daylight White Light IMPORTANT - THIS IS A LARGE BULB THAT MIGHT NOT FIT STANDARD HOUSEHOLD LAMPS, see diagram above; a larger lamp harp is needed to accommodate bulb base and width of 3 inches; dimensions: length: 7 inches; Width (Diameter): 3 inches; fits all medium-base E27/E26 sockets Crisp, bright white daylight ideal for reading and tasks that require visual accuracy, flicker-free; CFL bulb has natural daylight balanced color temperature of 5500K Good for starting plant growth; generates very little heat Energy saving, uses about 1/4 of the energy of a comparable Tungsten bulb, with 2800 Lumens output at 120V; about 8,000 hours bulb life Important: ALZO CFL bulb life is based on the bulb in an open air fixture with sufficient ventilation; when ALZO bulbs are installed in fixtures that lack adequate ventilation, the life of the bulb will be reduced.