Thin, light, and highly durable, Edelrid's Viper 9. 6mm Climbing Rope is a perfect introduction to the world of lightweight performance ropes. It weighs just 60 grams per meter, so it won't slow you down when you're going for the send, but it also has an extra thick sheath 45% of the rope's mass for increased durability and safety. It doesn't catch quite as many falls as a result, but the added durability is key if you're planning on using the rope often, or you don't want to spring for a super fancy cord. It's not all basic, though, because the Viper still features Edelrid's Thermo Shield treatment, which gives it serious flexibility and smooth handle for easy feeding out and clipping.