Petzl Verso Belay Rappel Device - The VERSO Belay Rappel Device by Petzl is their lightest with Adaptive Rope Control technology (ARC). The VERSO is a simplified version of the REVERSO. It offers a lighter and more compact option for climbers looking to reduce the size and weight of their gear. The V-shaped friction channels, with asymmetrical lateral grooves, adapt the friction for better control. This ARC technology adapts to the diameter of the rope used by increasing or decreasing the braking friction on the rope according to its diameter and condition. This offers increased friction on thinner ropes and friction efficiency with larger diameter ropes. The asymmetrical grooved sidewalls decrease friction when taking in slack for greater ease of use. The rope friendly design of the VERSO separates the two strands of rope when belaying with half/twin ropes or while rappelling, thus helping to prevents kinks. Stiff keeper cable will not get sucked into the device and keeps it in the optimal position while also helping to prevent dropping it. A usage diagram is engraved on device for ease of use. The super compact design of the Petzl VERSO Belay Rappel Device makes it easy to use and doesn't take up much space on your rack.