This adapter sleeve provides a mechanical fit between a shaft with a plain cylindrical surface and a bearing bore machined with a taper, allowing the bearing to be mounted at any position along the shaft without requiring a stepped or threaded seat. The sleeve has a bore diameter of 90.0 mm and a net mass of 1.895 kg, and is produced in standard design. Fitting is achieved by driving the sleeve axially under the bearing and securing it with a locknut, which draws the inner ring up the taper to generate the correct internal clearance reduction. This design suits applications where the shaft is plain and easy alignment or dismounting of the bearing is required, since the sleeve simplifies positioning compared with a directly interference-fitted bore.