The BIRDS-AWAY Attack Spider® is a battery-operated device that will chase away damage-causing woodpeckers. Activated by sound, the spider drops down on an 18 inch string while making a loud noise. Then it climbs back up the string, ready to attack again. This unusual solution is both very inexpensive and highly effective. Woodpeckers cannot stand them!Unique, effective solution to woodpecker damage. Sound-activated. Drops fast when woodpecker pecks.