Amana Tool uses only the finest industrial quality precision ball bearings available. Bearings are double steel-shielded for extra rigidity and to inhibit dust. A special high-performance, high-temperature grease is used for maximum life., #47715, diameter (D) 0.492, cutting height (B) .195 (3/16), shank (D) 3/16, application new Undersized 1/2" Diameter bearing for use after resharpening. Fits all tools such as flush trims, B .195 (3/16), D 3/16, 47766 ultra-glide high performance ball bearing 61/64 overall DIA x 1/4 inner DIA x 3/8 radius