I am thinking 1930 to 1940

Is it all metal? I have seen the round ones at car shows but none like that one.

Round one on ebay right now.
All metal, and a wrinkle finish, it has 2 separate rolls of paper, one to write notes on and the other for date Idem and cost in the skinny opening, Thank you for the link, the round one is cool also.. 8) I put some joy dish soap on it to see if the oil would come off but I did not want to hurt it, advised by my wife :D