This is a fibre handled 100mm Wenger Standard Issue (model 1951). These knives, with minor changes over the years, were issued to the troops of the Swiss army between 1891 and 1961. This one is from 1954.
The ’54’ stamp on the blade means this knife was issued in 1954.
The circular stamp on the handle is the W-K stamp, which means WaffenKontrolle. This means the knife passed the Swiss army quality inspection.
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