wire-back hat buttons

[JohnK83882]

Even though hat buttons have been screwback mostly through the 20th century, I occasionally see these wire-back items that I assume are hat buttons. The design is the 1917 great seal so not 19th century. I do see this in police and fraternal hats. Are they for hats or gear? Any info is appreciated. 

 

[maddog1129]

My dad's WW II service cap had wired buttons and held the chinstrap.

[JohnK83882]

Right. They hold on the chinstrap. Maybe it depends on the maker of the hat.