Interesting AE dial

[Icefire]

A current auction on ebay has this AE dial with a number 10 and the Letter A. Is this common? I'm still new to this, and have not seen this version.
http://tinyurl.com/pdvoxfg

[G-Man]

Not at all uncommon since A.E. also manufactured custom dials for the military and industrial users.

In fact, the scoreboards at my old high school used a control panel with A.E. dials and step switches so the boards could be located on the football field and high upon the gym walls.
One favorite use by the military and broadcasters alike was for the remote control of transmitters over telephone lines.  They could change the power output, switch to different antennas, frequencies, turn them on or off, etc.
Some of these dials had normally open pulsing contacts, and/or had different make/break ratio than standard telephone dials.