Original Item: Only One Available. This is an impressive original U.S. Model 1918 Mark I trench knife manufactured during WWI by Landers, Frary & Clark of New Britain, Connecticut, and later paired with a scarce 1943-dated M6 leather sheath during the WWII period.

The knife measures approximately 11 3/4 inches overall and features its unmistakable cast-brass knuckle grip and 6 3/4-inch double-edged dagger blade. With the sheath, the overall length is approximately 12 inches.

The U.S. Mark I was one of two official patterns of trench knife used by American forces during WWI. The Imperial War Museums identifies Landers, Frary & Clark as one of the manufacturers of the pattern.

Developed for close combat in the confined conditions of trench warfare, the Mark I combined a sharply pointed dagger blade with a heavy brass grip designed to protect the hand and provide an additional striking surface. Its aggressive appearance and specialized construction have made it one of the most recognizable American fighting knives of either world war.

The cast-brass grip is clearly marked:

U.S. 1918
L.F. & C.
1918

The grip and knuckle guard retain a substantial amount of their original darkened finish. Areas where the finish has worn away reveal aged brass with a deep, attractive patina.

The four finger openings retain their pointed projections, while the conical pommel remains present at the rear.

The pommel appears to be seized in place and was not forced or removed. This has allowed the grip and blade assembly to remain undisturbed, although it does not by itself establish when the components were assembled.

The double-edged dagger blade measures approximately 6 3/4 inches long.

Some of the original factory grinding remains visible. The blade was cleaned at some point, and much of the original darkened finish has worn or been removed.

Scattered oxidation spotting, surface staining, and handling scuffs are present, particularly near the ricasso. We could not locate any significant edge nicks.

The Mark I was designed during WWI, but surviving examples remained in American inventories and continued to be carried during WWII. The later leather sheath accompanying this example is consistent with that extended service life.

The knife is housed in an original 1943-dated U.S. M6 leather sheath. The M6 was introduced during WWII for the M3 trench knife, making its association with the earlier Mark I an unusual and highly appealing field-modified configuration.

The edges of the sheath throat were cut diagonally to provide clearance for the Mark I’s unusually wide brass guard. Wear at the throat, belt hook, and upper leather body indicates that the knife has rested in this sheath for an extended period.

The underside of the eight-staple metal throat is stamped:

U.S. M6
… CO.
1943

The manufacturer’s name has been deliberately scratched away and is no longer legible. We are therefore unable to identify the sheath maker conclusively.

The throat retains the standard eight-staple construction.

The leather body is assembled with stitching, rivets, and a double-sided reinforcing plate at the lower end. Unlike some M6 variations, it does not have additional staples positioned along the stitched edges. This construction may eventually help identify the original manufacturer, although no firm attribution is currently made.

The leather retaining strap remains present and is in very good condition.

Its snap fastener functions properly, and the rear wire belt hook remains intact.

The back of the leather body has been scratched with the initials: S.L.L.

No identity has been established for the individual represented by these initials.

The sheath shows wear consistent with prolonged association with the knife. The brass pommel has rubbed against the upper belt-hook area, while the broad guard has produced substantial wear directly above and around the modified throat.

Although this wear suggests that the knife and sheath have been together for many years, the exact date when they were paired cannot be determined.

Landers, Frary & Clark was established in New Britain, Connecticut, during the 19th century and became a major manufacturer of cutlery, tools, appliances, and household goods. Its products were widely marketed under the Universal trade name.

During WWI, the company also manufactured military equipment, including the triangular-bladed Model 1917 trench knife and the double-edged Model 1918 Mark I.

The Mark I was manufactured in the United States by Landers, Frary & Clark, Henry Disston & Sons, and Oneida Community Limited. A separate French-made version is marked “Au Lion.”

The American-made knives were originally supplied with blackened blades and brass grips. Much of that finish was inevitably lost through wartime use, cleaning, and decades of handling.

This example retains considerably more dark finish on the brass hilt than many surviving Mark I knives, while the blade displays the honest wear expected of a weapon that saw a long service life.

The M6 sheath adds another layer of interest. Rather than remaining with its original WWI metal scabbard, this knife was adapted for use with a WWII leather sheath, likely because the original scabbard was unavailable, damaged, or no longer considered practical.

The modified throat, wear caused by the guard and pommel, scratched initials, and removed maker name all contribute to the character of the pairing.

The combination of a genuine L.F. & C. Mark I trench knife and a modified, 1943-dated M6 sheath is substantially more unusual than a loose knife or a standard M3 and M6 combination.

With its fierce brass knuckle grip, retained dark finish, full dagger blade, personalized sheath, and clear evidence of extended military-era use, this is a visually commanding example of an American fighting knife that bridges both world wars.

Specifications:
Manufacturer: Landers, Frary & Clark
Model: U.S. Model 1918 Mark I Trench Knife
Period of Manufacture: WWI
Blade Length: 6 3/4"
Blade Style: Double-Edged Dagger
Knife Overall Length: Approximately 11 3/4"
Overall Length with Sheath: Approximately 12"
Guard Dimensions: Approximately 4 1/2" Long × 3 3/4" Wide
Sheath: U.S. M6 Leather Sheath
Sheath Date: 1943
Sheath Length: Approximately 8 1/4", Plus Belt Hook