... Architectural Perforated Aluminum Railings---Round Perforations - Non-Standard Finished End Pattern/ Round Perforations - Minimum Margins/ Round Perforations - 45 degree PatternSquare ... , Tapping(threading), Shearing(pressing/punching), Insulation (thermal break), Platic forming(bending/stretching), Hydroforming4) Mechanical Surface Treatment: Grinding, Anodizing, Painting, Power coating ...