Originally Posted by Bro. Dave

I hope it isn't bad form to piggyback on to this thread, but it made me remember an old knife I have. It has a metal sheath.
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It has the "U.S.N." "Mark I" on one side and "RH -35" with an oval in between that says " PAL Made in USA

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This knife was in my father-in-law's toolbox when he died and no other family member had any interest in it at all. I feigned disinterest, but grabbed it quickly.
Any information will be more than I have (although I haven't googled yet).