Regimental badge

From Memory Alpha, the free Star Trek reference.

A regimental badge was a military insignia that indicated the regiment to which a soldier belonged.

Regimental badges were worn by soldiers in the Cardassian Guard. In 2373, Crewman Boq'ta found a regimental badge on the dead body of a Cardassian solider in a broken stasis tube onboard Empok Nor. The badge indicated that the soldier belonged to the First Order, Third Battalion. Boq'ta mentioned how the find would be of interest to Crewman Pechetti, who collected such insignia and emblems. (DS9: "Empok Nor")