This is the Case CA7125 Russlock, an officially licensed “Ducks Unlimited” knife (operating conservation since 1930).
The knife is just over 4 inches long (when closed), with a stainless steel linerlock and Tru-Sharp surgical steel blade with a handy thumb opener (called a Russ lock) which is cast as an extension of the blade, and extends over the tip of the handle for easy thumb access.
The English Walnut handle looks delightful and is finished with Nickel Silver bolsters and a Ducks Unlimited shield. Simply brilliant – another amazing example of the kind of work that the W.R.Case Cutlery company do.