8 x 12 x 3.5 Sealed Stainless Steel Ball Bearing One Bearing 8 x 12 x 3.5 Stainless Steel Ball Bearing, Bearing is Made of Stainless Steel, bearing has 2 Rubber Seal to protect the bearing from dust or any possible contamination, inner diameter is 8mm, outer diameter is 12mm and width is 3.5mm.