Sterling's Evolution Helix is a favorite among intermediate-to-expert sport climbers due to its surprisingly high fall rating for a rope with a skinny, light 9.5mm diameter. Despite having a high fall rating, ropes with skinnier sheathes tend to wear out faster due to weather and abrasion. The Evoloution Helix DryXP Climbing Rope features the new DryXP treatment, Sterling's first treatment that actually meets UIAA's water-repellency standards. DryXP practically eliminates water absorption and drastically increases abrasion-resistance. The result is a climbing rope that you can project hard sport climbs with a lot longer than Sterling's untreated Helix.