Flexo is an abbreviation of flexography and flexo printers can print on many types of surfaces including plastic, metallic paper and food packaging. Technical details of flexo printers and the history of their development can be found on Wikipedia and there are videos on youtube showing how they work.

C I flexo have max TIR of ±4 microns.

1955-1958. This was my father's business in Traverse City.

You can basically get those anywhere. Your best shot would be at your local pharmacy. If you have no luck there then you can ask your foot doctor to order them for you.

According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 2 words with the pattern --EX-. That is, five letter words with 3rd letter E and 4th letter X. In alphabetical order, they are:

flexo

prexy