A flyswatter is a 10-letter control device pest used to swat away flying insects. A servo is a 5-letter control device pest that is an electromechanical device used to control the movement of a mechanism or system. RADAR is a 5-letter control device pest that uses radio waves to detect the presence, direction, and distance of objects. Lastly, a REIN is a 4-letter control device pest that is a long, narrow strap attached to the bridle of a horse, used by the rider to control the animal's movements.