bat-gauge prop help

[rsaffle]

Hey gang, I'm working on designing the Bat-Gauge to 3d print and need some help to make it as accurate as possible. Does anyone have a picture or even an idea of how the bottom portion looks? Is that a knob or a slide at the bottom? I got this screen grab that looks like it could be a button and I found this drawing by an artist on the web but I don't know if he just guessed at what it looks like or not.

I'm not sure if this device ever appeared in other episodes or if the prop showed up online. I also hope to draw up the explosive he used with this. Any help is appreciated.

[Batfanman]

I don't know for sure but it looks like it might be a rotary switch knob. As an aside, my first reaction to the photos above is that it looks like it was made from/like a utility belt box.

[A. Pennyworth]

the Bat-Gauge seems to be just square on the bottom with a glint of silver/flash in perhaps another lamp? maybe within a side ribbed knob?

The explosive is simple, note the red and light blue wires and the 2 whatever they are sticking up off the round blue cylinder

[Batfanman]

I also think that the yellow tubing may have been a necessity to run lines to power those lights and that he may have had a battery system on his belt out of sight.

[Batfanman]

I fiddled with the contrast a bit and cropped it to that area and it does looks curved like a flat disc knob.

[A. Pennyworth]

just shows the gauge bottom in this grab.

[rsaffle]

Awesome help guys! That last photo by Pennyworth really shows the shape of it. Weird how the rotary knob looks silver though? I think its just catching the light. I'm leaning towards it being a round flat faced switch knob with side ribs in all black. It's gauge shape is definitely large enough to house batteries without going into the tube but they may have had to do that back then. It's also interesting that Batman holds the explosive on the back of the gauge like they attach but that is probably just the way it ended up. In theory, I guess both pieces should fit into a belt pouch or two but it doesn't look like either would to me. I think I'll add a belt clip on both...maybe.

I've done most of the design already. I'll get as close as possible, but I thought I did that on my last prop and then better pictures showed up and showed me different stuff. I knew you guys would know if its ever been shown in greater detail before or not.
Appreciate the help Batfanman and Pennyworth!

[Batfanman]

You're welcome - and yes, that knob is catching light from the ring above. It's probably a black knob and in case it's not clear enough, the body of the gauge is navy blue.