99502-2RS Full Ceramic Ball Bearing Zirconia 5/8" x 1 3/8" x 7/16" inch 99502-2RS Full Ceramic Ball Bearing, the inner diameter is 5/8" inch, outer diameter is 1 3/8" inch and the width is 7/16" inch, this is a popular size that could be used in many applications, Bearing is made of Ceramic.