Swiss-Made Hardened Stainless-Steel shanks are made from heat-treated stainless steel, maintaining the strictest tolerances on shank diameter and making them vibration-free. Highly specialized coating process more than doubles the strength of the diamond bonding to the surface resulting in superior performance and enabling sharp, long-lasting, smooth cutting ability. Accurate Preparations in Less Time: The exceptional diamond coating process more than doubles the strength of the diamond bonding to the shank for superior performance enabling Zendo's SELECT Diamond burs to cut smoothly and rapidly, leaving a sharply demarcated preparation.