I’ve tried this on a FB site that concentrates on Norwegian helmets, but no result yet. So we’ll see what You Lot have got to say. It is an interesting thing anyway.

On first glance it looks like a Swedish M26. It has the small crest along the centre line of the shell that is found on the Swedish M21 and the Norwegian M31.

The chinstrap is rivetted, not sewn as seems to be normal for the M31. Also, it seems identical to a type of strap used on the Swedish M26.

It has the metal liner band of a Swedish M21 - or a Norwegian M31. The metal liner band is not identical to that which I see in photos of the M31, but is more like that of the Swedish M21. The liner pads are not sewn to the liner band, as in in the M31, they are held by split-pins.

It does not have an applied rim, and there is no sign there ever was one that has been removed. There is no sign that a frontal crest, either Swedish or Norwegian, was ever in place.

There are no markings or stampings of any kind on shell, liner, or strap.

I am really confused. This helmet seems to have the characteristics of three different types. It is always possible that is has been assembled from parts, but perhaps there is another answer.

Click to enlarge the picture