The buffer zone combines a "sterile zone" created between two lines of concertina barbed wire fences and a high taut wire fence, which acts as a "trip wire" for alerting on possible penetration, A deep mobility obstacle, and patrol roads on both sides complete the physical dimension of the buffer zone. Several companies are providing the fences, including Magal, Elbit's Detektion division both provide the touch sensitive fence and Moserot, which provides the concertina. Other companies are currently bidding for the supply of complementing systems, which should improve the effectiveness of the buffer zone, while deploying much smaller forces, dramatically reduinge the life cycle cost of the project which have already absorbed close to US$ 250 million per 120 km.