Vintage MYSTERY KNIFE from an estate sale.  Four blade. (knife, saw, spike, screw driver)
 
Im not sure of the maker.  The logo has a bright diamond. The handle also has two marks that I am not familiar with.
 
Condition:  Wasnt used much if at all. Signs of being opened and closed only. No cracks or chips on handle. Still has its loop.
 
Location E2