Tubular belay devices are the perfect companions for the belayer who needs a simple yet super effective device. The loop of rope passes through the holes and is then clipped with a carabiner to the harness. Arresting a fall is done by holding firmly the rope. Tubular belay devices have one or two holes through which a single rope or a pair of twin or half ropes can pass and can also be used for belaying the second climber. Some of them can also be used for rappelling.