... flatness not exceeding 3mmApplicable Scope: Motor part, Mechanical part, Machine tool, Hardware product, Valve, Pump valve, Electro-mechanical equipment, ... USB port or Serial port (6) Several sets of Marking Machine can be controlled by One Computer via USB port. ... English letters, Arabic numbers, Vector graphs and Coders. Size of Letters: Adjustable Marking Speed: 100-7000mm/min (adjustable, marking ...