Ruptured Duck Pin
The Honorable Discharge Lapel Patch originated in 1919 at the close of World War I.
The purpose of the patch, and later pin, was to permit Honorably Discharged military personnel to wear their uniform for a period of time after they left military service due to the lack of immediate access to civilian clothes while at the same time identify themselves as no longer being active duty personnel.
Also, during and immediately after World War II, clothing was still rationed so the masses of discharged military personnel had only their previous civilian clothing at home or their uniforms to wear.
The pin version of the patch was intended to permit civilian dressed, honorably discharged personnel to identify their former military status easily when applying for work or veteran's benefits.