The 5558382-1: The housing carries a board lock and panel stops, plus a keying feature that prevents inserting a non-keyed plug. An EMI finger on the shield bleeds common-mode noise to the chassis ground before it reaches the signal pairs — useful in industrial panels where variable-frequency drives or switching supplies share the cabinet.
The Cat3 rating limits this jack to 10BASE-T and voice applications — the internal wiring and crosstalk margin are specced for 16 MHz signaling, not the 100 MHz of Cat5e or the 250 MHz of Cat6. For a 10 Mb control network or a POTS line in a backplane, the 50.0µin gold and the shielded housing give you a solid, noise-bleeding interconnect that will outlast the equipment.
Through-hole solder termination with the board lock holding the part in place during wave or selective solder — the lock anchors the shield ground and keeps the right-angle body from lifting under cable strain. The keying tab and panel stops register the jack in the cutout so the EMI finger contacts the panel edge consistently. Single-row, single-port layout; the tab faces down when the jack is mounted on the top side of the board.