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here are a couple of thread about file razors
http://straightrazorpalace.com/workshop/30523-handle-idea-nonfolding-razor.html
and...

i have shaved with a razor that had been rework from a file and it was a fine shaver. old files are usually great steel and when they wear out it is good to re-purpose them... several custom makers...

I am only guessing but that does look like a repurposed file.