JustPet Dog Wireless Fence Training Collar has the powerful abilities of signal transmission and penetrating force. The product is the centered on the transmitter, and transfer the signal to all of the directions. Using the signal in open air, the distance of signal could achieve 2000 feet. And using it indoors, the signal transmitter is less affected by the house and kinds of different household appliances. When the dog goes out of the signal range of the transmitter, the receiver will issue a warning. Warning method: first, vibrate for 3-5 seconds, then static electric shock for 3-5 seconds. If the dog does not return to the safe area after working in a cycle twice, the receiver will keep sounding a warning tone until the dog returns to the safe area.