i searched on a competetor, and this is all i found
Take advantage of the latest in fluorescent light technology. HIGH OUTPUT T-5 bulbs housed in a slim hanging fixture ideal for reef aquariums. Innovative reflector maximizes light output and T-5 bulbs distribute light evenly across the length of your aquarium for uniform lighting conditions. Features non-corrosive extruded aluminum housing, internal electronic ballast, reflector, protective glass lens, and two 72" cords. Includes steel wire hanging kit and 4-54 watt Aquablue (60% actinic blue, 40% 11000°K) T-5 HO bulbs. 48" x 8" x 3" high. 216 watt (4-54 watt bulbs). Replacement bulbs sold separately.High output
All the ones i found said high output. I didnt find any for NO. So i think that they; were just talking about t-5 in general to say that it was high-output.... but i do not know