Whether it's a limit-testing onsight attempt, a 5. 14 redpoint, or a wandering alpine climb, the Mammut Serenity Dry Climbing Rope is your secret weapon for success. With a diameter of just 8. 7mm and weight of just 51 grams/meter, the Serenity boasts one of the lightest and thinnest designs of any single rope available today. It's also fully certified as a half and twin rope, making it suitable for long alpine routes, and it has a dry-treated sheath and core so it won't absorb water on alpine, ice, or mixed routes.