I couldn't find an American vendor for this style of raceway for the wire harness in my virtual pin cabinet project, so here we are. 16mm x 16mm x 250mm long when assembled. Print in multiples of two, with the open "U" up gives good strength to the fingers when assembled. I plan to mount these with a good quality double sided tape, but there's no reason why someone couldn't drill holes and use screws or brads to mount if wanted.

Railcore II 300ZL

.4mm

I printed my tests pieces in PLA, but using something with a little more flex would benefit the ability to insert and remove wires after it's installed.