641937-1 is an MTA-156 series 3-position vertical PCB header connector designed for wire-to-board applications. It features a 3.96 mm contact centerline spacing, friction lock mating mechanism, and square copper alloy contacts with tin plating. The header is rated for 7 Amps current and 600 VAC voltage, with a PCB thickness compatibility of 1.60 mm and solder tail post length of 3.18 mm. The natural-colored polyester GF housing meets UL 94V-0 flammability rating, making it suitable for reliable power and signal connections in various electronic assemblies.