SR166ZZ High Speed Ball Bearing 3/16" x 3/8" x 1/8" inch Stainless Steel Premium ABEC-5 7 Solid SI3N4 Ceramic Balls High quality Speed Premium ABEC-5 Bearing that fits many applications. Stainless Steel bearing with 7 solid SI3N4 Ceramic Balls, Bearing is made of Stainless Steel and has Solid Ceramic balls (SI3N4).