Features: 1.POWER INDICATOR: Dog barking deterrent device with low battery indicator, use the function button when the battery is low, the indicator will turn red. Use 9V battery (not included) power supply, stable and energy saving. 2.ULTRASONIC: Barking deterrent from 15Hz to 120kHz. Emits 25kHz ultrasonic, above the range of human hearing, but tends to attract the attention of dogs and make them feel uncomfortable with the push of a button. 3.2 FREQUENCIES: The ultrasonic bark deterrent emits 2 different types of ultrasonic, a steady frequency of fluctuating frequencies and an irregular frequency of ultrasonic. Avoid your dog getting used to simple frequencies by choosing different types. 4.LARGE RANGE CONTROL: Handheld bark control device that fits perfectly in your hand. 16.5ft control range for easy outdoor use, corrects dogs' bad behavior in public and guards them from unsafe food, also deters other dogs from approaching you. 5.BEEP BUTTON: This dog bark stopper has a beep function button that also helps correct bad behavior by pressing this button before each ultrasonic emission, allowing your dog to establish conditioned reflexes without ultrasonic punishment. Specification: Item Type: Dog Barking Deterrent Device_x000D_ Material: ABS_x000D_ Size: Approx. 10 x 4.2 x 3.7cm / 3.9 x 1.7 x 1.5in_x000D_ Color: Black White_x000D_ Battery Type: Dry Battery_x000D_ Battery Type: 9V Battery (PPP3 Battery) (Shipped without Battery) PackageList: 1 xDog Barking Deterrent Device 1 xInstructionManual Note Manual measurement, please allow some errors.