What this header fits
The 1-640384-5 is a 15-position, single-row, unshrouded header from TE's MTA-156 series. The 0.156" (3.96mm) pitch matches the MTA-156 IDC receptacle family — the same series that uses the matching crimp contacts and housings for board-to-cable/wire assemblies.
Sizing the current for your wire
The current rating is not a fixed number — it varies by wire gauge. The header itself is rated for 600VAC, and the tin-plated contacts handle standard signal-level currents in the MTA-156 system.