Feature: Ultrasonic design: Based on the theory of ultrasound, the dog trainer can effectively train your dog to be obedient and prevent some undesirable behaviors, such as barking, chewing, digging, etc. Wide range of applications: very suitable for training all kinds of dogs, such as pets, police dogs, shepherd dogs, Samoyed, border collies, shepherd dogs, etc. Easy to operate: first open the battery cover, then put in a 9V battery (not included), only pets can hear the sound, and finally open the switch to work normally, they can also be used as flashlights if necessary. Multi-function: In addition to being a pet training tool, it can also prevent you from being attacked by dogs, suitable for outdoor work, travel and night security patrols. Note: Do not deliberately tease the dog with the dog drive, because it is not surprising that the dog listens more.