[ARC5] Transmitter question

[Jack Antonio]

Thanks to a kind list member, by search for
a black BC-458 is over.  The set will need a little
work, but not too serious.

There are some markings on the transmitter that I'm
curious about.

On the top cover, there are two places that say in white
ink, " A-20-G " surrounded by a rectangle.  There is also
a rectangular marking saying "TESTED BY " with the date of
Sept 7, but the year is illegible.

The question concerns the A-20-G marking.  I'm wondering
if this really refers to the A-20 attack aircraft, or does
it have some other significance?

Anyone else see a similar marking?

Jack Antonio WA7DIA/4