for Touch Door Knob Entry Alarm Alert Security Anti Theft

brand new and high quality
OOTDTY  
Requires no special wire
Just hang on the inside door knob, open the the piercing alarm will scare off any unwanted intruders, leaving you and your home well protected
120 supper loud alarm ringing
Size:99mm x 55mm x 27mm(approx)
Powered by a 9V battery(not included)