A bit of research reveals that cat 5 structured wiring is 24AWG single strand
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It also seems that MOST patch leads are in fact NOT solid core, but stranded with the RJ45 plugs being designed specifically for this...but its been so long since I made up a patch lead that I cant remember anything beyond the fact that once they got cheap, pre assembled, we never made one up again, as they were a constant source of trouble.