Premium Sprocket 6-hole. 101 Octane Premium sprockets are laser cut in Europe using thermo-mechanically rolled fine-grain steel ALFORM 460 EN 10149 and therefore have a better, wear-reducing tooth geometry with optimum strength. Laser cutting ensures a significant weight reduction and a unique design. An impact-resistant KTL coating also protects against unwanted scratches. The durability of these sprockets is 2-3 times higher than conventional sprockets.