I am selling this item because it is no longer needed, having been used very little after opening. Here is the product description: This device uses a sound (ultrasonic) to get a dog's attention for training. The ultrasonic sound is difficult for humans to hear, but easily heard by dogs. You can train your dog without raising your voice. The intensity can be adjusted. It is lightweight and compact, operating on a 006P 9V battery. A light indicates when the device is activated. I have confirmed that the pilot lamp lights up when testing the item before listing. *Batteries are not included, so please prepare them yourself.