Multi-row angular contact roller bearing comprising an inner ring which is not divided in the axial direction and an outer ring which is not divided in the axial direction, between which two or more raceways (112, 112'; 122, 122') for a multiplicity of rolling elements (140, 140') are formed, the rolling elements (140, 140') being adapted to roll in their respective raceways (112, 112'; 122, 122') in the circumferential direction of the angular contact roller bearing, and wherein - the respective raceways (112, 112'; 122, 122') and the rolling elements (140, 140') comprise at least approximately a cross section corresponding to one another, - a cross-section of the rolling element (140, 140') containing a central longitudinal axis of a rolling element (140, 140') has a rectangular shape and an imaginary diagonal (d1, d1') through the cross-section of the rolling element (140, 140'), which diagonal (d1, d1') is identical for all the rolling elements (140, 140') on a raceway (112, 112'; 122, 122') of the angular contact roller bearing; 122, 122') of the angular contact roller bearing on an imaginary surface, the rolling element (140, 140') having a length and a transverse dimension extending transversely to its central longitudinal axis, and - a ratio of the transverse dimension of the rolling element (140, 140') to its length is characteristic of an angle (alpha) at which the raceway112, 112'; 122, 122') of the rolling elements (140, 140') is inclined to the central longitudinal axis of the angular contact roller bearing, wherein the ratio of the transverse dimension to the length is less than 1 and the surface is frustoconical, wherein the raceways (112, 112'; 122, 122') machined into the inner ring and/or the outer ring are open on one side flank, characterised in that, in the case of an O arrangement of the angular contact roller bearing, only an inner lateral flank of the raceway machined into the inner ring -and an outer lateral flank of the raceway machined intoouter ring have a respective shoulder, against which a respective end face of the rolling element rests, and wherein an outer side edge of the raceway machined into the inner ring and an inner side edge of the raceway machined into the outer ring project beyond the respective end face of the rolling element in the direction of its longitudinal centre axis; and wherein, in the case of an X arrangement of the angular contact roller bearing, only an outer lateral flank of the raceway machined into the inner ring and an inner lateral flank of the raceway machined into the outer ring each have a respective shoulder against which a respective end face of the rolling element bears, and wherein an inner lateral edge of the raceway machined into the inner ring and an outer lateral edge of the raceway machined into the outer ring project beyond the respective end face of the rolling element in the direction of the longitudinal centre axis thereof. - the respective raceways (112, 112'; 122, 122') and the rolling elements (140, 140') comprise at least approximately a cross section corresponding to one another, - a cross-section of the rolling element (140, 140') containing a central longitudinal axis of a rolling element (140, 140') has a rectangular shape and an imaginary diagonal (d1, d1') through the cross-section of the rolling element (140, 140'), which diagonal (d1, d1') is identical for all the rolling elements (140, 140') on a raceway (112, 112'; 122, 122') of the angular contact roller bearing; 122, 122') of the angular contact roller bearing on an imaginary surface, the rolling element (140, 140') having a length and a transverse dimension extending transversely to its central longitudinal axis, and - a ratio of the transverse dimension of the rolling element (140, 140') to its length is characteristic of an angle (alpha) at which the raceway112, 112'; 122, 122') of the rolling elements (140, 140') is inclined to the central longitudinal axis of the angular contact roller bearing, wherein the ratio of the transverse dimension to the length is less than 1 and the surface is frustoconical, wherein the raceways (112, 112'; 122, 122') machined into the inner ring and/or the outer ring are open on one side flank, characterised in that, in the case of an O arrangement of the angular contact roller bearing, only an inner lateral flank of the raceway machined into the inner ring -and an outer lateral flank of the raceway machined intoouter ring have a respective shoulder, against which a respective end face of the rolling element rests, and wherein an outer side edge of the raceway machined into the inner ring and an inner side edge of the raceway machined into the outer ring project beyond the respective end face of the rolling element in the direction of its longitudinal centre axis; and wherein, in the case of an X arrangement of the angular contact roller bearing, only an outer lateral flank of the raceway machined into the inner ring and an inner lateral flank of the raceway machined into the outer ring each have a respective shoulder against which a respective end face of the rolling element bears, and wherein an inner lateral edge of the raceway machined into the inner ring and an outer lateral edge of the raceway machined into the outer ring project beyond the respective end face of the rolling element in the direction of the longitudinal centre axis thereof.