Thought these deserved to be posted...
All four pairs from the X-Metal plants QC dept...
The red stickers on the Mag Switch are supposed to be QC labels but I cannot see any problem with them...
The Copper and Blue Pennys have no serial number. The Mars is a standard non Crater with serial matched box with the low number of M000081.
I have spoke with several forum members, some who have pairs that share the same 'heritage' as these so I am 99% sure they are from the Dayton Plant...