I was helping out a friend clean up his garage and came upon a Kinfolks 315 knife (7 1/2") over all length. It was just sitting in an old can of junk, sheath old and worn but knife in very good condition. Cant find any info about knife am interested in its value. It was my friends fathers knife that passed away a few years ago, he thinks its from the 1940's! Never heard of this brand of knife! Thanks

I know about Kinfolks only because I have one or two Kinfolks bayonets.

You should be able to go through the old catalogs online and find your knife.
http://kinfolksinc.com/mission.htm

Founded in Little Valley, NY in 1927 Made sheath knives, household knives, razors, hatchets and pocket knives most being sheath knives and during WWII they made lots of military knives! Their knives Were marked KINFOLKS USA, JEAN CASE or J. CASE and closed in 1948. In 1958 trademark bought by Robeson cutlery - they made 10 designs but only had an etched stamp until 1965 when Robeson sold to Cutler Federal.
During the 90's Tennessee River Valley Knife Association made knives with the KINFOLKS stamp but aren't related

a pic will tell the story, have collected kinfolks up to 70's