This full spectrum light bulb creates daylight balanced lighting, is energy star compliant, and has a long life of cir. 6,000 hours *) with 4250 Lumens output; low energy consumption, used in light therapy for treating S.A.D. (Seasonal Affective Disorder), for photo studio lights, or for starting plant growth. This is a Compact Fluorescent Light (CFL) bulb. Fits all medium-base E27/E26 sockets. Dimensions: L: 10.5"; W (Diameter): 3.9"; Length socket base to top of ballast: 4.5"; W (diameter) of socket: 1". *) ALZO CFL bulb life is based on the bulb in an open air upright orientation. When ALZO bulbs are installed in fixtures that lack adequate ventilation, the life of the bulb will be reduced. If an ALZO CFL bulb is installed in an overhead recessed light fixture with the bulb glass below the base, the life of the bulb will be greatly reduced. ALZO warranty for all CFL bulbs is 30 days.