Our bearing have high quality low noise & conpetitive price! Certificates: ISO 9001: ... .(AISI)52100—American,(Din)100Cr6—Germany.2) Shield/closure: open bearing, Z, ZZ, RS, 2RS.3) Vibration and Noise level: Z1 ... : Tube packing, individual box packing.8) Certificates: ISO 9001:2000 pillow block bearing