FAQ
How are screw-in CFL, pin-base CFL, and GU24 different?
Screw-in CFLs have threaded ends that screw in to the fixture's sockets. The power supply that operates the CFL is called a "ballast." Screw-in CFLs are also referred to as self-ballasted CFLs because the ballast is integrated into the lamp as a non-removable part. Screw-in CFLs do not meet California's Title 24 requirements.
Pin-base CFLs, like those used in our Pin-Base Compact Fluorescent Lighting section, have small plastic bases with 2 or 4 pins. Pin-base CFLs only fit fixtures specially designed for them, and are typically used in large commercial settings. Pin-base CFLs comply with California's Title 24, but they have fixed wattage that cannot be changed, and should not be confused with newer GU24 base bulbs.
GU24 CFLs combine the GU24 base with a CF bulb. Bulbs are easy to install with a quick twist-and-lock action, making them ideal for residential use. GU24 bulbs provide good-quality light, are highly energy efficient, and are compatible with California's Title 24.