The peak and transverse reinforcement have been lost.
The ear protectors have been raised out of the helmet.
A carrying handle was fitted (there are two rivet holes).
The bottom three illustrations appear to show that the helmet has been restored, as compared with the photograph in the Robinson publication for this helmet.
References:
Robinson, H.R. (1975), "The Armour of Imperial Rome", (Arms & Armour Press), p.98, No.266-8
Klumbach, H., (1974), "Römische Helme aus Niedergermanien", (Bonn), p.44 & Taf.31
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