Thicker than the arm used for horizontal activities, this arm can hold short zip lines that are up to 150m long. Each zip line requires the use of 2 arms, one at the beginning and another on the other end of the wire rope. While assembling, wire rope must be maintained with 2 ferrules "h" per arm. Made for a 7x19 12mm or 1/2" wire rope or a 6x7 12mm lang forming in case of heavy traffic.