This adapter sleeve provides a tapered mounting interface for fitting a bearing with a tapered bore onto a cylindrical shaft. It has a bore diameter of 40.0 mm and a net mass of 0.233 kg, in standard design, supplied as a complete mechanical unit (FP) ready for fitting. The tapered fit allows radial clamping of the bearing inner ring onto the shaft, which sets the operating internal clearance during mounting and removes the need for a shaft shoulder or keyway at that location. Axial position on the shaft is adjustable, allowing correct clearance to be achieved by controlled advancement of the sleeve during assembly, and the sleeve simplifies dismounting when bearing replacement is required.