A Nilos ring is an external metal bearing seal that produces a small labyrinth like sealing surface on the inner or outer ring of a bearing. When mounted in pairs, the bearing is sealed for life. Nilos rings, which can be used with or without integral bearing seals, are available in galvanized steel, stainless steel and brass. The material that you choose depends on the application and the operating environment. Galvanized steel is especially good in environments where there are tough abrasive particles. Stainless steel is usually used in food processing environments, and other applications where water or other corrosive materials are present. Brass is used in applications where there are high concentrations of salt or other corrosive solutions. Specifications Inner Diameter: 115mm Outer Diameter: 165mm Width: 121mm