Place the PetSafe Pawz Away Outdoor Pet Barrier in any area you want your pet to avoid. The Barrier Transmitter, disguised as a rock in your landscape, sends a circular radio signal to your pet's Receiver Collar. When your pet enters the Barrier Area, he'll hear audible tones from the Receiver Collar followed by a safe, progressive Static Correction. The correction is delivered through the Contact Points of the collar that touch his neck. He'll quickly associate the correction with the area you've declared off-limits. Barrier Transmitter disguised as a rock blends seamlessly into your landscape. Electronic signal creates "off -limit" areas for your pet. Protects an area up to 16 feet in diameter with no wire. Create a custom shaped barrier up to 150 feet using a boundary wire (sold separately). Lightweight Receiver Collar featuring Progressive Static Correction. Adjustable collar fits pets 5 lbs. and larger, appropriate for neck sizes 6" - 28".