Ball Bearings 6304RS 20 x 52 x 15 Lot of 10 Bearings High Quality 10 Ball Bearings 6304RS, 6304RS the inner diameter is 20mm, 6304RS outer diameter is 52mm and the width is 15mm, 6304RS is a popular size that could be used in many applications,6304RS Bearings are made of Chrome Steel and can rotate up to 10000 rpm, 6304RS bearing has Rubber Seals to protect the bearing from dust or any possible contamination, 6304RS bearings are pre-lubricated with grease.