CFL Bulb Shapes:
CFLs Are available in different sizes and shapes to fit in almost any fixture, for indoors and outdoors. The following are the most common shapes and styles:
Spiral: They are the most popular type of Compact Fluorescent Lamp (CFL). Spiral CFLs are made in several sizes to fit most common fixtures. You can replace most of your traditional bulbs around the house with spiral CFLs. Their light casting qualities are similar to incandescent lights however consuming a lot less energy.
Three-way and Dimmable Spiral CFLs: If you want to fit a fixture with a dimmer switch, you have to make sure you buy a dimmable CFL. Similarly, fixtures with three way switches require the use of a three-way CFL. Make sure the package you buy clearly state either the word dimmable or three-way. Dimmable CFLs maintain their white color better than incandescent lamps which turn yellow as they dim. However, while incandescent lights dim to no output, dimmable CFLs dim to 10-40% of their original brightness. Both three-way and dimmable CFLs typically come in soft white color temperature.
A-Shape CFLs: These look much like the traditional incandescent lamps, a CFL spiral lamp with a dome cover. Consumers who do not like the spiral look will find the A-Shape CFLs a more familiar look with the same spiral CFL energy saving features. Their light is also similar to the “soft white” of incandescents.
Globe CFLs: They are ideal for use where the bulb can be seen, such as in bathroom vanity mirrors or open hanging lamps. A Globe bulb is a spiral bulb with a decorative cover. They generally provide a soft white light.
Daylight CFLs: Daylight bulbs have a color temperature of at least 5,000 degrees Kelvin, which produces a very white daylight-like light. These bulbs are screw-in with a standard/medium E26 base.
Candel CFLs: These bulbs are ideal for use in smaller decorative fixtures where you can see the light bulbs such as chandeliers and sconces.
Indoor: Perfect for providing directional light such as recessed ceiling lights in kitchens or ceiling fans. Indoor bulbs are much smaller than outdoor reflector bulbs and can be dimmable for use with a dimmer switch.
Outdoor: These bulbs are built to withstand the elements. It is advisable not to use the outdoor reflectors with timers and motion sensors as this use will shorten the life of the bulbs.