1-87348-0 is a modular header assembly designed for single-row vertical mounting applications with 0.100 inch centerline spacing. The assembly features 0.025 inch square posts manufactured from phosphor bronze material with a 0.015 inch total runout specification. Posts are finished with bright tin-lead plating (0.0001–0.0002 inch) over 0.00005 inch nickel, or alternative finishes including bright tin or matte tin over nickel as specified. The header accommodates 40 positions with dimensions of 3.984 inches length and 3.900 inches width, providing reliable electrical and mechanical connections for printed circuit board applications. This connector type is commonly used in industrial control systems, test equipment, and modular electronic assemblies where standardized 0.100 inch pitch interconnection is required.