Needle roller bearings are a type of rolling-element bearing that utilizes slender, cylindrical rolling elements known as needle rollers. The length of these rollers is at least four times their diameter. Due to their exceptional rigidity, needle roller bearings can support larger, stiffer shafts in specific applications. They offer a higher load-carrying capacity than single-row ball bearings or cylindrical roller bearings of comparable outside diameter. To save space, the inner ring can sometimes be omitted, allowing the needle rollers to run directly on the shaft surface.