... roller bearing 1,Bearing steel GCr15 2,High quality and speed 3,Competitive price 2013 hot sale self-aligning cylindrical roller ... : d-20mm D-52mm5, Grease: 180006, Hardness: 59-65 Rc7, Speed: 3000-5000/ minute8, Service: OEM9, Certificate: ISO9001:200810, Sample: FREE11 ...