Mein kampf spine hook?

[Russer98]

Firstly I must apologise if my question is just me being ignorant.
I found a 1938 copy of Mein Kampf and it’s nothing special and a little worn but I noticed hidden down the spine cavity there is a 2 inch long metal hook/loop which pierced through to the middle of the book.Its made of a length of twisted steel with a small loop on the end.
What is it ?I’ve seen lots of old books before but never seen one of these
I hope someone can educate me Thanks in advance of any response.

[BlackWatch1]

Perhaps from a Sewing Press and it was forgotten when the cover was attached.

"Sewing Press.

If when the press is tightened one of the cords is loose, as will sometimes happen, a pencil, folding-stick or other object slipped under the lay cord on the top of the beam will tighten the band sufficiently. The foreign sewing presses have screws with a hook at the end to hold the bands, the screws running in a slot in the beam: in practice they are very convenient."

[Russer98]

Thanks for the quick reply Blackwatch1 that makes a lot of sense.I had wondered if it could have been a way of hanging the book in a store front but I think you could be right Thanks again

[panzer1432]

I have never seen that. Cool and unique.