WW2 enameled Division/ unit insignia

I bought a large grouping of these insignia several years ago and just "found" them again a few days ago.

I believe that they were made to attach to some sort of homefront item to show support for a loved one in a particular unit. I am not certain about the item-- maybe a lighter or jewelry item?

Shown with this group:

Tank Destroyer Battalion-- as the name implies (that is a tank the cat is eating).
82nd Airborne Division-- the US Army's first Airborne Division.
91st Division-- Segregated African American Division that fought in the Pacific theater.

Reproduction of these photographs in any form is not authorized.

scott