Camillus made the first USN fighting knife. The knife had a heavy, threaded butt and because of minor design flaws was promptly returned to the factory. Camillus redesigned the knife, replacing the threaded nut with a steel pin. The new design was deemed acceptable, hence the designation "USN Fighting Knife, Mark 2." PAL, made these knives under contract during WWII. The USMC version made by KA-BAR of Olean, N.Y., became so well known that this style of knife is still called a "Kabar" by army and Marine Corps ground troops, even if it's a cheap "Made in Taiwan" copy.

After the war, the Mark 2 was made by Utica, Camillus, and Connetta. All told, at least 20 different types, (denoted by slight design differences and makers markings on the blade) of this design were manufactured under a Department of the Navy contract. The USMC fighting utility knife (aka "Kabar") is the same as the USN Mark 2. KA-BAR (Union Cutlery Company of Olean, N.Y.) made around a million of the robust and versatile knives. Camillus Cutlery Company of Camillus, N.Y., is the other well-known manufacturer of the USMC fighting utility knife and continues to make this blade to its original specifications. The Remington Cutlery Company was bought by the PAL Blade and Tool Company (Plattsburg, N.Y.) shortly before WWII. PAL continued with the Remington line, including marking the blade with the old Remington numbering identification - "RH" for Remington Hunting-followed by a model number. The RH-36 had a six-inch blade and the RH-37 had a seven-inch blade.

During WWII, PAL's entire production was military knives. Their USN Mark 1 was marked RH-35 and their USN Mark 2 was marked RH-37. The RH-36 is an interim type design with a 6-1/2 inch blade with a parkerized finish and a pinned aluminum butt cap. The handle is of the very common leather washer type and the knife's overall length is 11-1/24 inches. PAL also made their RH-37/USN Mark 2 with a USMC stamp as a fighting utility knife as well as producing the M-4 bayonet knife, the M-3 Trench knife, and M1 Garand rifle bayonets. KA-BAR, besides making the famed fighting utility knife for the USMC (all blades of this type were called "Kabars" by the soldiers and marines who carried them and, as mentioned previously, the practice continues today) also made USN Mark 2s. One variation which was supposedly issued to the Navy's Underwater Demolition Teams (UDT) has a seven inch unmarked bright finished blade without "blood groove" or blade handles rather than the normal segmented leather washer handles. The guard is marked "KA-BAR; USN/MK 2." This knife and another similar Mark 2 meant for underwater work were issued with the USN/MK2 scabbard with a gray molded plastic body and a gray webbing hanger.

These knifes were used by Navy SEAL and UDT teams, often with Mk13 Mod 0 Signal Flare taped to the scabbord.