These are Compact Fluorescent Light (CFL) bulbs that fit all medium-base E27/E26 sockets, but the large bulb size might create a fit problem with standard lamp harps of household light fixtures; a larger lamp harp is needed, see ASIN below.
Dimensions: L: 6.5 in; W (Diameter): 2.25 in; Length socket base to top of ballast: 2.75 in; W (diameter) of socket: 1 in. Also available as a 15W bulb, see ASIN below.
*) 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.
• ASIN B0035LTIZE; 9 in lamp harp
• ASIN B0089MIH8I; 15W Joyous Light Full Spectrum bulb