The only handles ever found on helmets are very simple
types, fairly squared in profile instead of rounded, usually diamond cross-section, and with a simple terminals/ends.
Unfortunately, the exact same
type found on the few surviving helmets are found much, much more often associated with boxes and furniture.
So sadly all we could say with the specific squared off
type is it could be either helmet or box/furniture and odds are the latter.
Some authors have claimed that the
dolphin handles were also used on helmets (again they are also 100% known from boxes and furniture) but I have never been able to find an image of an authentic helmet found with an
intact dolphin handle and every
dolphin handle I have seen has ends that are too thick to be useful on helmets.
The
type shown in this
thread were attached (soldered ??) to the item. That would be odd for helmets as they would not bend or rotate and would make carrying the helmet very awkward.
SC