The PetSafe Stubborn Dog Collar is for the Occasional "Hard-Headed" Dog. This is the most powerful dog fence collar available With FIVE LEVELS OF CORRECTION PLUS VIBRATION as an added deterrent. This is a true breakthrough in pet containment. <bR>Ideal for extremely hard to train dogs, or Dogs that are consistently breaking through the boundary and need a stronger receiver. <BR><br>Five Levels of Programmable Correction plus a vibration feature in the warning tone as an additional deterrent.<BR>***Level one is warning only with vibration - ideal for initial training or very timid pets.<BR>***Levels two thru four are for easy or average to train pets.<BR>***Level five is for very hard to train or stubborn pets.<p> Progressive Correction - if your pet attempts to leave the yard, the receiver will automatically increase the correction level until he returns.<br>Anti Linger so the dog cannot stay in the warning zone and run down the battery.<BR>Levels are easily changed with a push of a button on the receiver.<P> Safety features include: <BR>***Protection against false activation - Only our transmitter can activate the receiver. No false activation from Televisions, cordless phones, garage door opener etc. <BR>***Receiver Fail-Safe - If your pet gets trapped in the correction zone, the receiver will shut down after 20 seconds to protect your pet. <BR>***Receiver with adjustable collar. <p> The PetSafe Stubborn Dog Collar is for the occasional hard-to-train dog and is compatible with all PetSafe, Radio Fence and Pet Guardian Brand underground dog fences EXCEPT UltraSmart Rechargeable In-Ground Fence (PIG00-13619) and YardMax Rechargeable In-Ground Fence (PIG00-11115). <BR>Also compatible with the Indoor Pet Barrier Transmitter (PIRF-100) to protect your pet indoors. <BR>It weighs just 3 ounces and measures 2.25 x 1.5 x 1.25 inches. It is three times more.powerful than our regular dog fence collars and is designed with stubborn or hard to train dogs.