Board footprint and series fit
The 643495-1: This is a 5-position, single-row header from the MTA-156 series, with a 3.96mm (0.156-inch) pitch that sets the board footprint and confirms compatibility with standard MTA-156 receptacles. The body is shrouded on one wall — the open side faces the board edge, which helps guide the mating housing during blind assembly. Only 4 of the 5 positions are loaded with pins; the empty position is common in MTA-156 headers for keying or to reduce contact count in a standard cavity layout.
Current, plating, and mating cycle reality
Through-hole mounting and termination
The header mounts vertically through-hole with solder termination. The contact length — mating portion is 0.400 inch (10.16mm), post length is 0.125 inch (3.18mm), and overall contact length is 0.650 inch (16.51mm). The housing is natural-colored, glass-filled thermoplastic. Contact material is copper alloy, square pin shape — standard for MTA-156 headers.