A needle roller bearing is a special type of roller bearing which uses long, thin cylindrical rollers resembling needles. Ordinary roller bearings' rollers are only slightly longer than their diameter, but needle bearings typically have rollers that are at least four times longer than their diameter. Like all bearings, they are used to reduce the friction of a rotating surface. Needle bearings have a greater surface area in contact with the races, so they can support a greater load. They are also thinner, so they require less clearance between the axle and the surrounding structure. Specifications Bore Diameter: 0.8750 In Outside Diameter: 1.1241 In Width: 1.2600 In Material: Chrome Steel Series: Mi Minimum Radius: 0.0400 In Lubrication Hole 200 kN GR RS, GR RSS, GR S, GR SRS, MR RS, MR RSS, MR S, MR SRS, GR 18 SS, MR 18, MR 18 SS Not Rated Open 5300 RPM Separable Inner Ring Only - Heavy Duty Needle Roller Bearing Steel