BEFORE PLACING YOUR ORDER CONTACT US SO WE CAN CONFIRM AVAILABILITY AND OFFER YOU A DISCOUNT CODE. YOU MAY DO THIS VIA CHAT OR EMAIL [email protected] SEND US THE PRODUCT NAME AND WE WILL PROVIDE THE DISCOUNT CODE. WE PREFER CHAT TO GET RESPONSE. Our pet training collar receiver is compatible with our dog fencing system. When your dog approaches the boundary, the signal causes the dog’s collar receiver to deliver a warning beep first. If your dog continues closer to the boundary, the collar will issue a mild shock. If your dog continues further, the collar will issue stronger shocks until your dog returns to within the boundary you have set up. Your dog will naturally seek to avoid correction, and is content staying within established boundaries. Keep safe in limited space. (Only Collar, Fencing System Not Included)