Features: 1. This Anti Bark Device will trigger after more than three times barking, effectively filter out some false triggering cause by environmental noise or dog occasionally bark. 2. Design by sound control and fitted on the wall, easy to install. 3. Come with a rotary wall holder, makes the device can rotate 360 degrees freely. 4. Human cannot hear the ultrasonic, NO harm to human and dog, safe to use. Specification: Material: Hard plastic Power Supply: DC 8.4V,500mA Power Adapter Input Voltage: AC 100V240V Plug type: US/EU/UK/AU Plug Size: 12.6 x 7 x 4.5 cm Color: As the pictures shown Note: Adjust the sensitivity: Using the slotted screwdriver from the back of the hole,Clockwise to turn it the sensibility will be high, otherwise counter-clockwise will be low Quantity:1 Set Item Type:Bark Deterrents-- Package List: 1 set x Wall Mounted Anti Dog Barking Control