The TE 5-557963-2 is listed as Obsolete on the manufacturer's lifecycle record. That means TE no longer manufactures this exact 10p10c RJ50 plug. If you have an active BOM line or a repair stock holding that calls out this order code, you are looking at the last-time-buy or surplus channel to fill it. No stock-holding claim on our side; the channel determines what is left.
The TE Connectivity 5-557963-2 is a 10-position 10-contact (10p10c) RJ50 modular plug. RJ50 is the less common 10-contact variant of the RJ-style family — most people know 8p8c (RJ45) for Ethernet, but 10p10c shows up in serial data, test equipment, and proprietary cabling where an extra pair or two is needed beyond the standard four. This plug terminates to round, stranded cable via IDC (insulation displacement contacts) — no stripping, no soldering, just a punch-down tool on site. The housing is translucent clear polycarbonate, letting you see the wire seating through the body. It is rated Cat5, which means it is certified to 100 MHz and supports 1000BASE-T (Gigabit Ethernet) signalling — not Cat5e or Cat6, so keep the data-rate ceiling in mind if you are pushing beyond that.
Contact arrangement is 10p10c — ten positions, all ten loaded with contacts. Wire range is 24-28 AWG stranded, round cable only — not solid or flat ribbon. The plug body itself is 0.895" (22.73 mm) long. No shielding on this variant; it is an unshielded plug for UTP cable.
Termination is IDC — the stranded wires are pushed into the slot contacts and the insulation is displaced by the metal tines. No crimp tool, no solder iron; a standard modular plug punch-down tool seats the wires. The plug mates with any standard RJ50 10p10c jack or receptacle — same form factor as an RJ45 but with the wider 10-contact body. If you are dropping this into an existing harness, confirm the jack on the other end is 10p10c, not 8p8c; the wider body will not fit an RJ45 jack.
Replacement and Cross-Reference Reality
The base product number is 557963, but the dash number (-2) specifies the exact variant — colour, plating, packaging. If you need a functional equivalent, you are looking for another 10p10c RJ50 plug with IDC termination, Cat5 rating, and 50 µ" gold contacts. Several manufacturers make RJ50 plugs that will mate with the same jack, but pin-to-pin compatibility and mechanical fit depend on the specific jack and cable type. The safest path is to source the exact 5-557963-2 through the surplus channel while stock exists, or qualify a parametric alternative against your specific jack and cable assembly.