This is
part of a weird belt system.
Two of these, one attached to each end of the leather belt, were attached by an S-shaped piece, often with animal
head ends.
I used to see them labelled as 6th-7th century, but Aleksander
Stanev dates them to the 4th century and shows many find places in Northern
Bulgaria in
his 2012 book Elementi na germaskiya fibelen kostyum na yug to dunav (
Germanic fibula and clothing elements from south of the Danube).
SC
