Dual black bulb system illuminates your fluorescent monofilament for easier visibility at longer distances. Frosted lens cover on the white general-purpose bulbs to reduce glare. The 4-way on/off switch lets you turn on just the lights you need. With the black lights on, fluorescent fishing line can be seen at a distance of 50'. Use either 6 D batteries (not included) or 12V electrical system. Complete with carry strap and 2 suction cup feet for temporary placement on the boat rail.