... .ZHY M And UM Type ER Wrench Hand Tool1.Three ER Wrench Hand Tool: type A, type M, type UM.2.Using SCM ... used to tool holders, to tighten the tool.4.ER A type hand tool: ER11A-BS, ER16A-BS, ER20A-BS.5.ER ... UM hand tool: ER25UM-BS, ER32UM-BS, ER40UM-BS, ER50UM-BS.6. ... ER M type hand tool: ER8M-BS, ER11M-BS, ER16M-BS, ER20M-BS, ER20M ...