Bearing Item: FR144ZZ Structure: Deep Groove Material: Bearing Steel Bore Dia (d): 3.175 mm 1/8 inch Outer Dia (D): 6.35 mm 1/4 inch Width (B): 2.779 mm 7/64 inch Closures: Metal Seal Lubrication: Grease Magnetic: little Hardness: 58HRC