(1 x Quality 2.2KW Air Cooled Spindle Motor ER20 ( 80mm, 220V/AC,400Hz,24000rpm,4pcs bearings,runout off<=0.01mm). 2.2kw Air-cooled spindle motor engraving milling grind. 2) When the spindle is temporarily not in use, should use compressed air to blow the coolant water,to avoid rusting, plug the hole.