There are three embossed ridges at the rear of the occiput. The crest holder at the apex of the crown is of the twist-on type. A hook is riveted at the front and back to secure the crest box. The neck guard also has a single embossed ridge.
The cheek guards have a hollow rim combined with a raised panel in the centre.
Courtesy Civico Museo Ala Ponzone, Cremona-IT - photo Roma-victrix.com
References:
Robinson, H.R. (1975), "The Armour of Imperial Rome", (Arms & Armour Press), p.66, Nos.155-9
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