After purchase, give the ejector pin.
Beginners without operational experience should use according to the instructions, tungsten steel features high hardness, high temperature resistance, wear resistance, never deformation, but the harder the more brittle, is a risk of damage, risk-free, careful choice. Any link used in machining is very important. Any error in any link will cause damage to the tool. Don't blame the tool with accurate size. (Before machining, carefully measure the precise size of the machining object, tool and punch reamer with precision caliper to avoid errors)