Daylight Replacement 18 watt Fluorescent Tube Bulb - This 18w bulb is specially made to simulate daylight, allowing for exact color matching. Equivalent to a 100w tungsten bulb. Easier on they eyes than regular bulbs. These are also cooler and emit less heat than regular light bulbs. It is 7-1/2 inches long and will fit into the Daylight Professional Artist Lamp #DTU33200.