6204-2RS-12 Sealed Ball Bearing 3/4" inch x 47mm x 14mm 6204-2RS-12 Sealed Ball Bearing, Bearing is made of Chrome Steel, each bearing has 2 Rubber Seals to protect the bearing from dust or any possible contamination, also bearing is pre-lubricated with grease, Bearing inner diameter is 3/4" inch, Bearing outer diameter is 47mm and Bearing width is 14mm.