Those are earring backs. Dan Crowley had posted the idea on a few other forums. I thought I would give it a try. They work great, although I will eventually go to a facia mounted knob with linkages to the turnouts. While the layout is in flux, they work great. I may actually keep them on the sidings and industrial trackage. I am going beyond Mr. Crowley's concept and am experimenting with using these in conjunction with slide switches, so I can power the frogs on my turnouts. I like the size and appearance better than the caboose Ind. throws, plus I can make 50 of them for a total of $5.75. I just spray bomb them black. The turnout has to be firmly in place, and a piece of roadbed placed under the throw, but they hold the points firmly.
Eric