... factor 3.low harmonic wave,good preheating start,. 4.fluorescent ballast FLOURESCENT BALLASTUnique design, slinky apppearance, portable ,compatct structure. ... , ceiling lighting, advertising lamp house,signboard lamp house.fluorescent ballast ModelYZ221DFA-CPower rising6minSize202x40x28mmInput voltage95-275VMogul attachable styleavailableOperation frequency50Hz-60HzColorfulAvailableinput ...