This adapter sleeve provides a mechanical fit between a shaft and a bearing bore that has a tapered seating surface, allowing the bearing to be mounted and dismounted without requiring a stepped or tightly toleranced shaft. The H2309 sleeve has a bore diameter of 40.0 mm, a net mass of 297.83 g, and is manufactured to the standard design. Using a tapered adapter sleeve allows the fitted bearing to be positioned freely along a plain cylindrical shaft, with the radial internal clearance set during mounting by axial displacement of the sleeve. This construction simplifies bearing removal for maintenance, since the assembly can be released by loosening the locking element rather than pressing the bearing off the shaft.