... 4,Noise level:Z1,Z2 5,C2,C0,C3.. Lily bearing is a specialized manufacturer of deep groove ball bearing with 72mm od.Features:1 ... C55),Material: AISI52100, AISI440C, AISI304, AISI316, Ceramic6),Retainer: PTFE, Nylon, PEEK Or Stainless Steel7),Bore Size:from 1mm to 10mm8 ... Seals Bearings Teflon Sealed Bearings Flanged Ball Bearings Thrust Ball Bearings Hybrid Ceramic Bearings Hybrid Ceramic Bearings