Our most popular light is the IR3 class 1 division 2 light. This light is used for many applications from: chemical storage areas, oil rigs, gas pipeline compressor rooms, ect. The IR3 4ft. T5HO and T8 versions are priced the same at $310 each. This is a very economical version of a classified light. They are made of aluminum body with poly lens. They are equipped with swivel brackets and come with 850 lamps. Please call or email us for any additional information on this light.