0.156" Pitch IDC Receptacle for Discrete or Ribbon Cable
The 3-643821-4: It uses a single row of female socket contacts on a 0.156" (3.96mm) pitch, with a closed-end housing and a polarizing key to prevent mis-mating. This makes the connector a fast option for point-to-point wiring in appliances, lighting, and control panels where 26 AWG signal runs are common.
Tin-Plated Contacts at 80.0µin — Moderate Cycle Life, Low Cost
The 3-643821-4 uses tin-plated contacts with a finish thickness of 80.0µin (2.03µm). The thick 80.0µin layer provides more wear resistance than thinner tin flash, extending the usable life in moderate-duty harnesses.