Petzl got its Volta Dry Climbing Rope certified for use as a single, twin, or half rope so you can climb crags, ice, big walls, or mixed alpine routes with the same rope. The Volta sports a skinny 9. 2-millimeter diameter and an ultralight weight (55 grams per meter) to keep elite climbers content. Petzl treated this rope with a Duratec dry treatment to resist water, dirt, and abrasion, and the treatment also provides better rope grip and handling in cold, wet conditions. This rope also has an UltraSonic f...