What is this unusual tripod for?

[68degrees]

I found this at goodwill for $5. Its all aluminum but I dont think its for cameras. Can anyone identify it? At first i thought it was just missing a piece but now I dont think so. I suppose I could modify it or make a camera mount out of wood or something but Im curious to know what it is actually for.

 

[Sejanus.Aelianus]

It is a camera tripod. You're missing the locking screw, which fits into T-slot of the platform.

Spare screws used to be common as muck but now might take some finding. You'll need one with a 1/4 - 1/3 inch shank between the screw and the head, the right size to slide freely in the T-slot.

 

[68degrees]

heres another pic of the bolt and wingnut