vmaniqui

here's what i gathered ONLINE regarding Chicago and Manhattan connectors. Apparently they are different from each other. nice blog about National Reversew "REX" (Model RUSA) Sewing Machine.

Sewing machine 2-pin plugs are probably all referred to as "Chicago" connectors by most people, but there's definitely two different sizes of them. The Manhattan type had rubber boots that slid over the bare electrical connections. The boots looked similar to the boot on an older style automobile coil wire on the distributor. On the "Chicago" connectors, the conductors are attached (wrapped) around the screws in plates, versus inserted into the end of tubes and secured with a screw threaded into the side of the tube as on the Manhattan [I remember working with a 4 pin version of the Manhattan connector. -ed].