The PetSafe In-Ground Deluxe Little Dog Fence containment system comes with a collar for small dogs.
Larger dogs can be added to this system by adding another collar.
How its works:
The containment area is made by laying wire in the desired perimeter configuration either underground or even on a fixed object, such as a fence. A radio signal is transmitted through the wire creating the boundary. Your pet will wear a receiver collar that send two types of signals to the dog. The first signal occurs when the dog approaches the boundary (Warning Zone)... the receiver collar will emit a warning beep. If the dog continues towards the boundary (Static Correction Zone), a second static correction signal will get his attention that the boundary should not be crossed. The PetSafe In-Ground Deulxe Little Dog Fence has the capability to cover up to 25 acres.