[Ron Ramirez]

It appears that 1939 and 1940 models used translucent wine pushbuttons; 1941 models use brown.

The 1939 pushbuttons are different from the 1940 buttons; they are wider on the back end and made to be retained with metal clips. The 1940 pushbuttons are made like the 1941 buttons, except that they are wine instead of brown.

A 40-150 or 40-155 table model set looks really cool in operation with a set of reproduction wine pushbuttons; the back lighting also lights up the buttons.