High efficiency and energy saving with built in ultra quiet inductive ballast or high efficiency electronic ballast ... with chip, PF≥0.99, THD<15%, life time is 30,000h, 110V/120V/220- 240V.50/60Hz,pre-heating ... for environment use solid-stated mercury, 38% less usage of glass and phosphor powder compared to T8 lamps.5, Good Color ... and so on T5 wall lamp fixtures built in EB 6w/8w/13w/14w/21w/28w/35w