1.Roller bearing sizes 2.Competitive price 3. OEM service offered 4. Low ... ,2. Bearing Details Linqing Yuanyi(UJK) Bearing Factory1MaterialChrome Steel Gcr15 , Carbon steel Gcr11 , Stainless steel2Grease/OilGood quality3CageSteel , Brass , Nylon4RollerSteel5SealOpen, Oil ... www.yy-bearing.comContact: Xingya Chen4. Bearing Pictures roller bearing sizes 31309 ,Chrome Steel Gcr15,Long life and low noise