DESC: The lightweight, waterproof collar receiver gives your pet one of four levels of correction, tone or vibration when the boundary is reached. Contain multiple dogs by purchasing additional receiver collars. The collar receiver has an anti-linger feature that prevents your pet from standing in the warning zone and depleting batteries. A low-battery indicator on the receiver collar and a wire-break alarm on the transmitter give you peace of mind the system is up and running. Pet Fences