... 10 years, maily export to Asia, and get high credit in customers all round the world.ZHY M ... heated jaw, have high hardness and toughness.3.It is used to tool holders, to tighten the tool.4.ER A ... end mills, carbide inserts, carbide rod, drill, reamer, tool holder, tool heads, chuck, collet, nut, etc.If you are ... will reply you at once, thank you! ZHY High Precision M And UM Type ER Wrench Hand Tool