The Petzl Reversino is a device for belaying the leader or the second, on skinny (8mm or less) double dynamic ropes. The rope runs easily without sticking for giving slack. By holding the free end it is easy to brake the rope and effectively hold a fall. You can attach it to the belay and change to belaying in autolocking mode. In this way, one or two seconds can be belayed independently. Finally, it can be used for abseiling. The Reversino is designed for multi- pitch climbs, mountaineering and ice-climbing specifically with twin rope set-ups. American Alpine Institute Guideschoice