640506-3 is a PC board vertical pin header designed for 36-circuit matrix miniature rectangular connectors with a 0.120 inch board thickness. This header features duplex finish plating with 0.000030 inch minimum gold in the mating area over 0.000050 inch minimum nickel underplate on the entire contact, combined with matte tin on the solder tail end. The header has a dimension A of 1.610 inches (40.89 mm) and dimension B of 0.180 inches (4.57 mm), providing precise spacing for high-density connector applications. It mates with socket housing part number 1-640526-0 and is RoHS compliant, making it suitable for industrial and commercial electronic assemblies requiring reliable multi-circuit interconnections.