Abstract: A motor-driven tubular hollow cylindrical partial mask component surrounds a central vertical blue light and rotates around the blue light. The hollow cylindrical partial mask blacks out a major portion of the blue light. A single vertical transparent slit in the partial mask admits blue light out to form a 360 degree scanning vertical beam of blue light as the partial mask rotates to attract deer flies, bell hornets and other flying insects. The flying insects enter through a surrounding exterior electrified cage to be electrically zapped and exterminated.