... -ISO9001:2008 approval Hardware Products Type A and M ER Nut With G6.3 Dynamic BalancingMaterial: SNCM-220 steel, ... for rpm10,000, and with patent.Not: please using ER-A spanner to tighten up. Should put the collet ... into nut when we use it.Type M ER Nut, outside diameter is small than standard nut, ... thread is different with type A.Other ER nut: type UM/RD, type KM/RD.Other products ...