The TE Connectivity 4-640426-6 is a 16-circuit MTA-156 receptacle that terminates 18 AWG discrete wire through an IDC slot — no stripping, no crimping, just a mass-termination press. The 0.156" (3.96mm) pitch gives each circuit enough spacing to handle the 18 AWG conductor without crowding the insulation, and the closed end keeps the wire from pushing through the back of the housing.
Termination and Wire Sizing
It is specified for 18 AWG discrete wire; the slot geometry and insulation displacement force are tuned for that gauge. Using a significantly different wire size risks an incomplete cut or a loose grip.
The locking ramp engages a ramp on the header to hold the pair together under vibration — you will hear it click when it seats. The single-row, 16-position layout means the connector is keyed by the header's polarisation rib; the receptacle itself is not polarised, so the header's keying prevents a reversed mate.