8x15x5 Shielded Ball Bearing One Bearing 8x15x5 Shielded Ball Bearing, the inner diameter is 8mm, outer diameter is 15mm and the width is 5mm, this is a popular size that could be used in many applications, Bearing is made of Chrome Steel, bearing has 2 metal shields to protect the bearing from dust or any possible contamination, also bearing is pre-lubricated with grease.