Needle Bearing is roller bearings with large length-to-diameter ratios in the rollers. This is utilised in tiny gasoline engines, gear pumps, small appliance and tool motors, alternators, aircraft controls, farm and construction equipment, and automobile transmissions. This particular style of roller bearing uses needle-like, long, thin cylindrical rollers. In contrast to needle bearings, which normally have rollers that are at least four times longer than their diameter, ordinary roller bearings feature rollers that are just slightly longer than their diameter.