This is a housing locating washer designed as a mating component for axial cylindrical roller bearing sets of the 811 series, working together with the K811 cage-and-roller assembly and the shaft locating washer WS. The outside diameter is 90.0 mm and the net mass is 109.6 g. As the housing-side raceway element, it provides the flat bearing surface against which the rollers run in a single load direction. Since the complete axial cylindrical roller bearing assembly separates into three individual rings, this washer allows the bearing arrangement to be mounted and adjusted independently on the housing side. It is intended for single-direction axial load support only, with the mating GS and WS washers selected to match the corresponding K811 roller and cage set for correct axial clearance and running accuracy.