Adapter sleeves are the most commonly used components for locating bearings with a tapered bore onto a cylindrical seat as they can be used on plain or stepped shafts (fig. 1 and fig. 2). They are easy to install and require no additional location on the shaft. When adapter sleeves are used on plain shafts, the bearing can be located at any position on the shaft. When used on stepped shafts together with an L-shaped spacer ring, bearings can be accurately positioned axially thereby facilitating bearing mounting and dismounting.