LED UL Type A U-bend lamps are plug-and-play to install into an existing fluorescent light fixture and operate from its ballast, so there's no need to rewire, add drivers, or modify electrical components. They allow a simple transition when upgrading from fluorescent lamps to more energy efficient, longer lasting LEDs. For proper operation, installers must verify that these light bulbs are compatible with fixture ballasts.

LED UL Type B U-bend lamps bypass the ballast and operate directly from a building's AC power. Also known as line-voltage lamps, they avoid the problem of faulty ballasts and drivers as well as the hassle and expense of adding drivers when upgrading from fluorescent lamps to more energy efficient, longer lasting LEDs. These ballast-bypass light bulbs require wiring into mains electricity, so they are not recommended for installations that frequently experience power surges or interruptions.