Crossed roller bearings are bearings for precision applications that correspond in their dimensions to ISO dimension series 18 in accordance with DIN 616. They comprise outer rings, inner rings, rolling elements and plastic spacers. The outer ring is split and is held together by three retaining rings.Due to the X arrangement of the rolling elements, these bearings can support axial forces from both directions as well as radial forces, tilting moment loads and any combination of loads with a single bearing position. This allows designs with two bearing positions to be reduced to a single bearing position. Crossed roller bearings are very rigid, have high running accuracy and are supplied with normal clearance, little clearance or preload. The bearing outer rings can be easily located in the adjacent construction by means of clamping rings.