We've never and never will be fans of electric collars or water spraying collars to supress barking. This device emits high pitch sounds undetectable to human ears and absolutely harmless to your dogs. Using this innovative device will teach even the noisiest of dogs that the postman isn't a threat.

Overview: 

Effective and efficent: An ultrasonic anti-barking device can automatically detect dog barks 50 feet away. The barking control device automatically emits high sounds that only dogs can hear. After the dog stops barking, the ultrasonic barking control will automatically stop emitting an ultrasound.

Harmless and safe: Ultrasound is harmless to pets and completely inaudible to human ears, so the device can be used safely.

Great battery capacity: Battery capacity of this device is 1600mAh. It is expected to be fully charged in 3-4 hours and can be used for 5-7 days.

Packing list:
1 x Anti-bark device
1 x USB cable
1 x Instruction book