【Range up to 50 feet. Anti-bark device】The sound penetration range is 50 feet, covering indoor and outdoor areas. Compared with traditional dog training equipment, your hands are completely free. You can easily train the dog's behavior by turning the knob. After testing, the best effect is within 50 feet. The smaller the range, the better the effect. 【Effective for most dogs】 The device works on most breeds and sizes, but not on deaf or hard of hearing dogs. Some dogs may be afraid or dislike the ultrasonic sound, so they may not stop barking at first. Please allow up to 2 weeks for training. 【Safe Bellstopper】Sonic is safe for pets. If the dog is hard of hearing or aggressive, the device may not work as intended. It is not recommended to use one device to stop two or more dogs barking at the same time. 【Simple and waterproof installation】 The device can be easily hung or mounted on a tree, wall or fence post to prevent your own or your neighbors' dogs from barking. Make sure the bark