The 15-watt 17.5-inch straight replacement lamp keeps your flowton fly control unit running efficiently. Yearly replacement is recommended to retain maximum black light output. The bulb is a 17.5-inch, 15-watt, high-intensity black light bulb, designed to work with the fc4900 model. The two bulbs are easily replaced through the front of the unit, no tools required, so replacement is quick and easy. This replacement bulb provides maximum luring power, so you can tackle bugs with the power to win.