... the flat surface 2.metal marking machine 3.pin marking machine 4.marking on the mechanical part Marking Surface: Flat surface or curved ... port or Serial port (6) Several sets of Marking Machine can be controlled by One Computer via USB port.Applicable ... Industry: to marking on Mechanical Part, Machine tool, Hardware Product, Steel Tube, Sleeve, Collar, Roller, Pump Valve, Ring Flange, Valve and ...