The best way visualize how these wireless systems work is to envision a dart board.Wireless Containment Systems Keeps pets within a circular area. The transmitter is positioned at a predetermined center. As the pet approaches the perimeter, they will be warned...if they continue they will receive a correction. Wireless Barriers or Zones Designed to keep pets away from an area or room They are designed to be used indoors. They can be very effective at keeping pets out of living rooms, areas near doorways etc. The transmitter is positioned so that as the pet approaches they will receive a warning...if they continue they will receive a correction.