【4-in-1 Bark Control with Multifunctional Modes】The ultrasonic dog bark deterrent combines 2X ultrasonic waves and a flashlight in one device, built-in fixed 25 kHz and variable 15-30 kHz frequencies, prevents excessive barking, chewing, and digging, can replace traditional electric shock collars and is safe and harmless to dogs. Suitable for indoor use, park, camping, picnic, and other scenarios.【2X Emitter Ultrasound & Humanized Design】The bark deterrent uses upgraded ultrasonic frequency technology with dual heads to enhance the ultrasonic coverage area and quickly stop dogs from barking. It does not cause physical pain or discomfort like electric shock collars, making it safer. It can effectively train dogs to stop barking and prevent neighboring dogs or large dogs from barking without causing harm.【15-meter Barking Distance & Compact Portability】The bark deterrent is compact in size and can be easily carried in your pocket or bag when you go out. Whether you want to quickly correct bad behavior or conduct daily obedience training indoors and outdoors in gardens and lawns, the anti-bark deterrent emits ultrasonic waves within 15 meters to quickly stop dogs from barking.【LED Light Mode and Enhanced Night Safety】Dog bark control devices are equipped with LED lights and a flashing mode, the bright LED lights guarantee your safety when walking at night. They can also act as a deterrent against aggressive or unfriendly dogs, providing safety and security when walking at night.【Type-C Rechargeable and Great 60-Day Usage Time】Dog bark deterrent devices have a built-in rechargeable lithium-ion battery and USB/Type-C charging port, 5V/2A rechargeable design, can be fully charged in 0.5 hours and can be used for longer up to 60 days after a full charge, with long standby time and are lightweight, suitable for daily use when training at home, walking, or traveling.