Plug-in CFL Bulbs Bases

Compact fluorescent Plug-In light bulbs have either 2 pins or 4 pins.

Each 2-pin lamp has an internal starter and is designed for preheat, magnetic operation.

The 4-pin lamps are designed for electronic ballast operation and are dimmable. These lamps have no internal starter; starting the lamps is a function of the ballast.

The following illustrations show some of the most popular Compact Fluorescent Plug-In bases:

Base Top Down Lamp Profile
2-Pin 1-Tube CFL
2-Pin 2-Tubes CFL
4-Pin 1-Tube CFL
4-Pin 2-Tube CFL
4-Pin 3-Tube CFL
4-Pin 4-Tube CFL