... of friction, high limiting speed, large size range and various structure.2.Features : Shield / closure: ... bearing, Z, ZZ, RS, 2RS,2RZBall bearings snap ring: N, NRTolerance codes: ABEC-1, ABEC-3, ... : PTFE, nylon, PEEK or stainless steelHardness for rings and balls: 59 - 63HRCBall bearings bore size: 1 - ... snap ring groove in outer ring N.With a snap ring groove in outer ring and external snap ring NR. ...