We have 2 nos Arrow Electrical surface outlet which is being taken out of the original shipping box - it is considered a duplex outlet and states it is 15 A - 125 V in Ivorylite.  This comes from an estate in CT where the woman tested/quality control from an electrical supply company.  I would estimate that it dates somewhere between the 1940's - 1960's or so.  Around each outlet/plug there is a decorative design on the outer edge.  The outlet plugs measure about 1 1/4" in W x 1 1/8" in L.  The full outlet measures about 3 3/4" x 1 7/8" x about 7/8" in depth - these were made to install outside of the wall on the wall or molding, I'm not sure if they would pass an electrical inspection if used in the current day.  They each have a small envelope with the screws.  The metal on the back is discolored on some from age. 

2 Electric Outlets nos Vintage Salvage