Croatia, Independent State. An Observer and Navigator Badge, by Braća Knaus certificate_of_authenticity painted in glossed black and

painted in glossed black and with matte black magnetic metal panels fastened to the sides with multiple rivets

a prime example

A Ustaski Lovac Arm Badge of the Ustasha Rifleman's Brigade - In die stamped aluminum

An M35 Double Decal Army (Heer) Helmet by  Emaillerwerk AG

Not much is known about the purpose of this badge

Croatia, Independent State. An Observer and Navigator Badge, by Braća Knaus certificate_of_authenticity painted in glossed black andConstructed of silvered bronze, the obverse consisting of knotted trefoil style wreath, joined together at the bottom by a red painted Croatian national emblem, topped by initials NDH (Nezavisna Drava Hrvatska Independent State of Croatia), overlaid by a Croatian national eagle with its wings fully outstretched, clutching three lightning bolts in its talons, the reverse with a barrel hinge and flattened tapering pinback meeting a round wire catch,