is Zip-cord rated that high (in voltage terms)?
Yes it is. I've used it for several cheapskate wiring projects that were supposed to look old (Basically a long piece of zip cord with a round ungrounded plug and an old brass light socket). Here in Austria they now print "42V max" on it, but I think there are several countries that still list zip cord for 220V.
Many old radios still have zip cord, as it is usually in pristine condition no one bothers to replace it.
