The Grivel Star Crack Gloves are the only gloves to feature Vibram's XS-Grip rubber, the climbing shoe rubber used by brands like Tenaya, Scarpa, and La Sportiva. Vibram XS-Grip ensures maximum friction on the rock – as good as the friction of your climbing shoes. Other features include a velcro closure covered with rubber to prevent rips and tears when jammed into abrasive rock. Grivel Star Crack Gloves