Specifications: In certain applications, the limited amount of space available for bearings and the loads to be supported require the use of a full complement of needles independent of any system of retention. The length of the needle is determined in relation to the load capacity required. The needles are placed directly between shaft and housing without the use of inner or outer rings. Thus a shaft of maximum diameter is permissible to increase rigidity and load capacity. In rotating applications where the load capacity requires the use of needles that are long in relation to the shaft diameter, it is preferable to employ two rows of needles of equal length separated by a spacer ring. In such cases, the needles must be selected with diameters in the same tolerance class. This arrangement is particularly recommended for mounting parts such as long idler wheels, especially where they are subjected to rotational torque.