Safe for Stop Barking and Training: the dog barking control devices come with an ultrasonic design that can produce 20-25 kHz of ultrasonic sound, which is safe for pets and humans, safely correcting unwanted behavior, stopping dogs from barking or preventing the eating of unsafe food, and can be applied both indoors and outdoors; Humans can’t hear the dog device that stops barking, but dogs can, and it will get the dog’s attention, but will not cause pain or irritation 25 Feet Range: the no barking device for dogs can reach up to 25 feet to deter unfriendly dogs, which is equipped with 800MAH rechargeable battery, can provide a full charge in 1 to 2 hours and can be applied normally for about 30 days Package Includes: you will receive 2 pieces of dog barking deterrents in black, which will have a vibration effect when you press the button, to bring you a better experience; The button indicator will get red when the battery is low Multifunctional Tool: the ultrasonic dog trainer designed with LED lights provide a method of deterring approaching dogs; Press the button to emit ultrasonic waves and quickly turn on the bright LED to flash and deter the dog; The flashlight can provide a bright light source when you are walking at night or in the low light condition place, keeping your safety in the dark, suitable for night dog walking Handheld and Portable: the handheld bark control device measures approx. 5.4 x 2.28 inch, which is compact and lightweight, equipped with a waist strap about 6.9 inch long, you can easily carry it outdoors