... approval Hardware Products Type A and M ER Nut With G6.3 Dynamic BalancingMaterial: SNCM-220 steel, with high aseismicity.Hardness: HRC52° ... , thread tolerance is 4H.Feature: With G6.3 dynamic balancing, suitable for rpm10,000, and with patent.Not: please using ER-A ... .Other products: carbide end mill, carbide inserts, carbide rod, tool holder, tool heads, chuck, collet, spanner, drill, reamer, etc.The ...