This is built extremely well. It does show you on any of the diagrams, but to wire it up.. Theres a little screw I the side. Unscrew that, and the whole jack socket slides out from the front, allowing you to solder to it. It works really well, and is just another great representation of Neutrik's flawless build quality and design.
I use this to extend the cable from my guitar, to my wireless receiver. I use a Strandberg Guitar (which is incredible by the way) and a Line 6 G10 Relay. The problem I was finding is, the little transmitter would slide its way out of the jack socket when pressed against my leg. So i've built a little cable to place the jack socket higher up on my strap so its not an issue.
This adaptor has allowed me to do that. Looks great in black to.