The 5-103166-4 is a standard profile double-row vertical shrouded header connector part of the AMPMODU 0.025 inch square interconnection system with 0.100 inch centerline spacing. This 12-position connector features shrouded design with specific dimensional characteristics: dimension A of 0.712 inches (18.08 mm), dimension B of 0.632 inches (16.05 mm), dimension C of 0.500 inches (12.70 mm), and dimension D of 0.206 inches (5.23 mm). The connector is designed for printed circuit board mounting with a recommended minimum board thickness of 0.055 inches (1.40 mm) and utilizes 0.035 ± 0.003 inch diameter contact holes. This header is commonly used in industrial control systems, telecommunications equipment, and modular electronic assemblies where reliable dual-row interconnection and compact spacing are required.