old wooden pole-side insulator holder brackets

Inspired by dav2no1's showing of a cool batch of glass and ceramic insulators, here's my little boxful of old wooden arms, threaded at one end to hold one insulator each, and otherwise made in an angled overall shape such to be fastened (with big ole' honkin nails, a couple of 'em still have one) near the tops of old wooden 'utility poles' to hold individual overhead wires.

I've had them for years, picked up someplace somewhere 'in the country' while otherwise exploring a ditch line or fence row or someplace like that I guess, I honestly don't remember. Came across 'em again recently...its probably about time I actually hang one or two back up somewhere around here...??