product manual:

The appearance of this product is designed like an alarm clock. The outdoor ultrasonic bark suppressor can be hung on a tree, anywhere in the house or in your yard, it can be hung, placed on a table or other places at will. When the luxury outdoor ultrasonic bark arrester alarm clock detects excessive barking, the microphone will sense the bark and activate the component. At this time, the product will emit a safe high-pitched ultrasonic sound that can be heard by dogs but not by humans. The dog will stop barking when stimulated by the sound. Because ultrasound will make the dog feel uncomfortable, the dog will stop barking.

Designed for outdoor use, the outdoor ultrasonic bark arrester is durable and waterproof. There are 3 levels of sensitivity (the effective range is between 4.5, 9 and 15.24 meters), and a test level. A 9-volt battery is required (not included), and the average battery life is 2 months. The outdoor ultrasonic bark arrester has a power indicator, which can be set to "Off" to protect the battery when you are away.

The use period is limited, and the warranty period is one year. Excessive barking of dogs can affect you and your neighbors. The outdoor ultrasonic bark suppressor can effectively stop the dog from barking and does not require a receiving collar. Safe and effective, suitable for dogs of all breeds and sizes.

Description: 
Material: ABS plastic
Color: Black
Product certificate: CE / RoHS FCC
Size: 16.5 * 15.5cm

Characteristic:
*Use ultrasound to stop dogs barking
*Effective range 50 feet
*Durable and waterproof
*Two color indicator light shows whether the power is sufficient
*9 V battery - (battery not included)
*Microphone sensitive to sound: trigger ultrasonic sound.
*Low sensitivity - short distance monitoring (15 feet)
*Medium sensitivity - (up to 30 feet)
*High sensitivity - high sensitivity (50 feet)

Package : 1 *Barking Silencer