641120-4 is an MTA-156 friction lock header designed for reliable printed circuit board interconnection applications. It features round posts with a .125 inch (3.18 mm) solder tail length and is finished with .000015 inch (0.00038 mm) gold plating over nickel on phosphor bronze material, providing excellent corrosion resistance and electrical conductivity. The header is constructed with UL94V-0 rated polyester housing in white and incorporates retentive leg design for secure mating with MTA-156 connectors. This component is commonly used in industrial control systems, telecommunications equipment, and data acquisition applications where reliable board-to-connector interfaces are essential.