Secures your home, dorm, office or hotel room from intruders with added security! As soon as the doorknob is touched, the alarm will sound like a powerful siren or barking dog to warn you that someone is trying to enter. An effective way to frighten away intruders. Easy no tool installation. Constructed of heavy gauge steel and uses one 9-volt battery (not included). Features include: For Added Security & ProtectionPowerful Siren or Barking Dog Sounds!Secures Your Home from Intruders!Alarm Sounds When Door Knob is Touched Heavy Gauge Steel ConstructionNo Installation RequiredProtects Any Room Any Time: Home, Dorm, Office, Hotel & More! Dimensions: 19.75 X 11.00 X 10.00 in.Includes retail packaging