The TE Connectivity 5555979-1 is a 6-position 4-conductor (6p4c) modular jack, wired for RJ11 or RJ14 telephone/data applications. It is the unshielded, right-angle through-hole member of the 5555979 series, with a single row of gold-plated phosphor bronze contacts rated for Cat3 performance — the standard for voice and low-speed data up to 16 MHz.
Through-hole solder tails provide stronger mechanical retention than SMT for a connector that sees frequent mating cycles. The tab direction is down, which orients the latch slot toward the board surface. The board lock is a pair of plastic or metal posts that snap into plated through-holes, holding the jack in place during the solder wave and preventing the connector from lifting under cable strain. For a part with no LED and no shielding, the board lock is the primary mechanical retention feature.
The 5555979-1 is an active TE Connectivity catalog item, sourced through independent distribution.