Size：M2，M2.5，M3，M4，M5，M6，M8，M10，M12，M14，M16，M18，M20. Sloted Self Tapping Threaded Inserts. Place the slotted or three hole end facing downwards, install the self tapping screw sleeve at the front end of the tool, press it vertically against the workpiece, turn the wrench, and turn it into the bottom hole.
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