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The Camillus Model 1760 "Demo" pocketknife, manufactured to U.S. Government Spec MIL-K-818D, first appeared in the mid-1940s and was issued to countless military personnel from World War II through Vietnam and beyond. An identical consumer version was advertised in the New York-based knifemaker's catalog beginning in 1946. And the Model 1760 was still there in 2006, the last Camillus catalog before the 134-year-old company collapsed into bankruptcy in 2007.
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A quick search of eBay just now uncovered at least a dozen such Camillus mil-spec pocketknives, even a few brand-new ones, ranging in price from $15 to $40. (I ignored one delusional listing for a well-used Camillus Demo, allegedly dated 1960, priced at $240. The seller noted no particular provenance. Sheesh.)
When a Swiss-made Soldier can be had new-in-box for 20 bucks, it might be difficult to justify paying twice the price for a comparable pocketknife made by a defunct American company.
On the other hand, it might not. Buyer's choice.
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Sharps: A modern-day Soldier
Sharps: Rite of passage
Sharps, Part I: In the pocket
Links
The Demo Knife
Notes
The federal government's NSN (National Stock Number) for the Camillus Model 1760 is 5110-00-162-2205.