Board footprint and mate compatibility
644753-4 is a 4-position, single-row header on 0.156" (3.96mm) pitch — the standard MTA-156 spacing. It mates with any MTA-156 receptacle housing that uses the same friction-lock keying.
Friction lock and vibration duty
The shrouded one-wall design includes a friction lock — not a ramp latch. That means the mating receptacle clicks into place with a push and stays put under moderate vibration, but it won't resist a hard yank on the wire. For high-shock environments, the MTA-156 series also offers a positive-lock version; this part is the lighter-hold option.