said by sempergoofy:said by robbin:Looks like there are holes for two wires for each screw on the back. As those are clamping connections there is no problem putting two wires to one screw.
One set of holes is for #12/#14 wire, the other is for #10 wire.
Both holes certainly look the same size in the pictures, even when you magnify them. Are you sure that each hole is rated for 10, 12 or 14 gauge wire? That would make a lot more sense and be quite common.