Designed for twin, half and single ropes. Lightweight and compact at only 65 grams. V-grooves for high friction when belaying the leader or rappelling. Self locking function when belaying the second climber. Eye-hole for releasing the self locking function if the second should fall or need to be lowered. with this device it is possible to simultaneously belay two climbers. for ropes 7.8 to 10.5 mm.