643493-1 is an MTA-156 header connector designed for wire-to-board applications with 4 contact positions and vertical PCB mounting. The connector features a 3.96 mm contact centerline spacing, square copper alloy contacts with tin plating, and a friction lock mating mechanism for secure connections. It is rated for 7 amperes at 600 VAC, with solder tail contacts made of copper alloy and tin plating, suitable for wave soldering processes up to 265°C. The housing is constructed from polyester glass-filled material with UL 94V flammability rating and is RoHS/ELV compliant. This connector is ideal for industrial control systems, power distribution modules, and other applications requiring reliable wire-to-board interconnections with high current capacity.