The closed-end housing acts as a positive stop for the cable during IDC termination, so the strip length and contact position stay consistent across a harness build.
IDC termination means the cable is pressed into the insulation-displacement slots — no stripping, no crimping. The 26-30 AWG range covers common signal-level discrete wire and standard 0.050" pitch ribbon cable. The free-hanging mount (in-line) suits it for cable-to-board or cable-to-cable harness runs where the receptacle is the female half. The closed end prevents the cable from pushing through the housing during termination, which keeps the conductors aligned with the slots.