... or curved surface with flatness not exceeding 3mmApplicable Scope: Motor part, Mechanical part, Machine tool, Hardware product, Valve, Pump valve, ... Cylinder Sleeve, etc.(2) Mechanical Industry: to marking on Mechanical Part, Machine tool, Hardware Product, Steel Tube, Sleeve, Collar, Roller ... letters with 0.5mm or Chinese letters with 0.8mm)Power Source: AC220±10% 50-60Hz (AC110V±10% 50-60Hz ) ...