Made from SCM-435 carbon-free steel and impregnated to guarantee zero breaking risk and extended sprocket life Ultra-hard surface layer (.5 mm) reduces friction to prevent power loss caused by chain drag Fully lightened with radial holes for off-road and street applications Grooved teeth for off-road applications, just like our factory racing parts, allowing fast dirt removal Real Factory Team specification parts from the company supplying real factory teams. SPROCKET FR CST-1579-16-2