These spherical bearings are offered in two grades, precision and commercial. Precision spherical bearings are manufactured to tight tolerances for applications requiring improved linkage accuracy and reduced looseness. Commercial spherical bearings are produced using standard materials and manufacturing methods and are an economical choice for industrial applications. Spherco® Spherical Plain Bearing, Series: FLBG, 1-7/8 in Inside Dia, 4 in Outside Dia, 52100 Steel