Inscription: Helmet with 3 plumes, letters F S; double-headed eagle displayed. Mark of Valentin Siebenburger.
Marking: Stamped with the makers mark of Valentin Siebenbürger.
Lazar, Tomaž. "An Armour by Valentin Siebenbürger in the National Museum of Slovenia." The Journal of the Arms & Armour Society 21, no. 2 (2013).