The 643464-5: This is a 7-position, single-row header from the MTA-156 series, with 6 positions loaded — one cavity is left open, which can serve as a keying feature to prevent mis-mating with a 7-circuit housing. The 0.156" (3.96mm) pitch sets the board footprint: each through-hole solder tail is spaced 3.96mm apart, and the 0.125" (3.18mm) post length is long enough for a standard 1.6mm PCB with a wave-solder fillet on the bottom side.
Locking and vibration duty
The shrouded - 1 wall design protects the mating pins from accidental contact and guides the housing into alignment during assembly.
Current and temperature envelope
At 105°C ambient, derate per the MTA-156 application note.