Product Features Self-centering function (prevention of slight off-center matters) Designed to suit relatively smaller hubs (as there is only small difference in dimension between inner(d) and outer(D) diameters, as well as its surface pressure is low) A wide range of standard inner diameters (from Ø5 to Ø50) Simple structure for easier installation & handier maintenance Diverse material & finish options available (e.g. stainless steel body for vacuum area, electroless nickel plating etc.)