Feature: 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 Material: ABS Size: Approx. 10 x 4.2 x 3.7cm / 3.9 x 1.7 x 1.5in Color: Black White Battery Type: Dry Battery Battery Type: 9V Battery (PPP3 Battery) (Shipped without Battery). Package List: 1 x Dog Barking Deterrent Device1 x Instruction Manual Note: Manual measurement, please allow some errors.