Technical Speedometer ID?

Can anyone tell me the application for this speedometer? It appears that the drive cable drives a little generator(?) which in turn creates voltage to turn the speedometer? Thanks for any help....Malcolm

 

show us the back of the speedometer?

 

See attached

 

I’ve seen old tachometers like that that attach to the crank snout .

I just can’t picture anything from that era that would need a 7 grand tach .


Oh , and I bet it’s off a dodge

 

it sure has that aircraft look to it with all the safety wire holes and the mil spec type connectors. Also the 4 tab mounting would be right...if only it were turned 45 degrees!

 

It is a speedometer....not a tachometer...I've seen another face that had the speed you could go in each gear...see attached......Thanks

 

I expect the big truck or whatever equipment it came from is not really a hot rod or custom?