Sterling's 9. 2mm Evolution Aero Dry Bi Pattern Climbing Rope gives you a superlight performance on sport, mixed, and ice routes. The Evolution Aero achieves an ultralight weight thanks to Sterling's innovative core construction that also allows for a smoother belay. Pair that core with a durable sheath, and you'll be enjoying this lightweight rope for a surprising amount of time. Sterling treated this Evolution Aero with DryCoat for water resistance, and a bi pattern design makes for an easy rappel.