Features:-Using advanced ultrasonic technology, it effectively stops dogs from barking excessively through four ultrasonic probes.-It features three adjustable ultrasonic intensity levels. It has a general-purpose irregular ultrasonic frequency of 15KHz-30KHz. 20kHz is suitable for small/docile dogs. 30kHz is suitable for playful/large dogs. Recommended for dogs aged 6 months to 8 years.-The effective range is 33 feet (approximately 10 meters). For best results, ensure there are no obstructions in the surrounding area.-It has a built-in rechargeable battery that can be fully charged in 2 hours via a USB interface. It can provide up to 30 days of continuous use. A red light indicates that the battery is charging, while a blue light indicates that it is fully .
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