RJ45 Coupler Teardown

I need to build a packet-dropper for work. I bought a sack of ethernet couplers, but they were surprisingly heavy. Molded into the case is "RJ45 Coupler" and "Cat 15A16A", neither of which are particularly descriptive.

Ages ago, they used to be lightweight beige plastic with stamped metal pins connecting from one side to the other.

So, I opened one of the new ones to find they use a tiny 2-layer circuit board now, and standard through-hole connectors. The traces aren't length-matched, but that probably mostly matters within each pair of signals. My handiwork has indeed damaged a few of the traces.

The circuit board isn't long enough to solder to the shield, so the shields are floating bits of metal, and this acts as a break in STP. Since the shields aren't soldered, they're usually held by the plastic molding. A few times I've run into really interesting uses of conductive rubber and plastics, but no, the meter says 20+ mega ohms.