Hot Rods What is it?

Anyone ever seen one of these? I was told it's a gauge for setting caster or camber ( I forget which). Found it at a yard sale.

 

It's for checking the angle of the dangle

 

Yard art.

 

Does it also show the "sag of the bag"?

 

HAHA! Left myself wide open.

 

I have no clue what it is, but I do understand WHY you had to have it! (It's just, well, cool.)

 

Every guy over sixty knows its a hoomerhingy, dumb ass kids.