Photo Courtesy Andreas Koch
Producer: Morse or Schrader ?
Type: screw in
Estimated age: around 1900
Total length: 34 cm
Blade: steel
Sheath: Solid brass
Handle: wood
Remarks: Similarly to the English diving knives of Siebe-Gorman

 
Producer: Morse
Type: Push in
Estimated age: 1910
Total length: 13 1/2 inches
Blade: Steel 1 side sharp
Sheath: Brass
Handle: Hardwood
Remarks: This style replaced the screw in pattern but preceeded the Mark V pattern which at this time had not been designed.

 


Photo courtesy of Alexy Byrgazov.
Producer: A. Schrader's Son
Type: Screw in
Estimated age: 1903
Total length: 34 cm
Blade: Steel 17 CM
Sheath: Solid Brass
Handle: Wood
Inscription: A Schrader's Son
Remarks: Handle made from 2 pieces of wood on has a stamp inside 1903

 
Producer: Desco
Type: screw in
Estimated DOM: 1940
Total length: 13 1/2 inches
Blade: Stainless steel 7 inches 1 blade serrated 1 blade
Inscription: MFD.BY BATTERYLESS TEL EQUIP. CO. INC PITTSBURG PA
Sheath: Solid Brass
Handle: maple wood
Remarks: none

 
Producer: Desco
Type: screw in
Estimated DOM: 1970
Total length: 14 inches
Blade: Stainless Steel length 7 inches 1 Edge serrated 1 edge sharp
Inscription: Desco on sheath
Sheath: none
Handle: maple wood
Remarks: Cost new in 1961 £2 14s

 
Producer: Vince
Type: screw in
Estimated DOM: 1935
Total length: 14 1/2 inches
Blade: Stainless Steel 6 3/4 inches 1 Blade serrated 1 blade sharp
Inscription: none
Sheath: Solid Brass
Handle: Dark maple wood
Remarks: Characteristic Vince loop diameter 1 5/8 inches , usual pattern diameter 1 1/2 inches

 
Producer: Vince
Type: screw in
Estimated DOM: 1935
Total length: 14 1/2 inches
Blade: Copper Beryllium 6¾ inches 1 blade serrated 1 blade sharp
Inscription: none
Sheath: Bronze
Handle: Dark Maple
Remarks: Has characteristic VINCE loop. Beryllium copper, also known as copper beryllium, beryllium bronze or spring copper is renowned for its high strength and non-sparking and non-magnetic qualities. It is resistant to oxidising acids and is abrasion resistant. The dust is highly toxic so anyone possessing such a knife should refrain from sharpening it.

 
Producer: Unknown
Type: screw in
Estimated DOM: 1930
Total length: 13 inches
Blade: Stainless Steel 1 Blade serrated 1 blade sharp
Inscription: none
Sheath: Solid Brass
Handle: maple wood
Remarks: Diameter of sheath 1 3/4 inches compared to 1 1/2 inches in later

 
Producer: Unknown
Type: screw in
Estimated DOM: 1945
Total length: 13 1/2 inches
Blade: Stainless Steel 1 serrated edge 1 sharp edge
Inscription: none
Sheath: none
Handle: maple wood
Remarks: Diameter of sheath 1 5/8 inches compared to usual pattern 1 1/2 inches

 
Producer: Morse
Type: screw in
Estimated DOM: 1998
Total length: 13 1/2 inches
Blade: Stainless Steel 6 3/4 inches 1 side serrated 1 side sharp
Inscription: Diving Equip.CO.ROCKLAND MA .02370 {with outline of helmet}
Sheath: solid brass
Handle: maple wood
Remarks: none

 
Producer: Desco
Type: screw in
Estimated DOM: 1960
Total length: 13 1/2 inches
Blade: Stainless steel 7 inches, 1 side sharp 1 side serrated
Inscription: DESCO on the sheath
Sheath: solid brass
Handle: maple wood
Remarks: none

 
Producer: Morse
Type: screw in
Estimated DOM: 1945
Total length: 13.58"
Blade: stainless steel, 6.69", 1 sharp side and 1 serrated side
Inscription: mfg'd by Morse diving equip. co. inc. Boston, Mass. USA on sheath
Sheath: solid brass
Handle: maple wood
Remarks: none

 
Producer: BM company
Type: put in
Estimated DOM: 1940
Total length: 13.18"
Blade: stainless steel, 7.08", one sharp side
Inscription: USN MK 2 and serial# on sheath. USN MARK 2 and Camillus N.Y on blade.
Sheath: synthetic material
Handle: wood
Remarks: 

 
Producer: BM company
Type: put in
Estimated DOM: 1940
Total length: 13.18"
Blade: stainless steel, 6.49", one sharp side
Inscription: USN MK 2 and serial# on sheath.
Sheath: synthetic material
Handle: wood
Remarks: 

 
Producer: Ontario, model number 497
Type: put in
Estimated DOM: Verified that it was issued to a navy servicemen as early as 1972
Total length: 10 3/4" (27.3cm)
Blade: 440 stainless steel, 15.2cm, one sharp and one serrated side
Inscription: MK 3 MOD 0 USN on sheath. MK 3 MOD 0 USN and serial# on blade.
Sheath: synthetic material, resin sheath with a drain hole at bottom Handle: non-slip resin Weight: 1 lb 2oz / 511mg
Handle: synthetic material with steel
Remarks: 

 
Producer: Scubapro
Type: put in
Estimated DOM: 1970
Total length: 11.80"
Blade: stainless steel, 6.29", one sharp and one serrated side
Inscription: stainless steel on blade
Sheath: synthetic material
Handle: synthetic material with chromed steel parts
Remarks: Photo courtesy of Diving Museum Lemmer, The Netherlands. This knife is now illegal. It was designed to stab.

 
Producer: Scubapro
Type: put in
Estimated DOM: 1980
Total length: 13.77"
Blade: anti-magnetic stainless stainless steel, 7.87", one sharp and one serrated side
Inscription: Scubapro A on blade.
Sheath: synthetic material
Handle: synthetic material with steel
Remarks:  Photo courtesy of Diving Museum Lemmer, The Netherlands.

 

Photo courtesy of Mike Burchett and Robert Burchett.
Producer: Imperial Knife Company.
Type: Put in.
DOM: 1961 (two small batches produced in 1981 and 1983).
Total length: 300mm (12 inches).
Blade: 187mm (7-3/8 inch) in length. Double-edged “dagger” form blade with one plain sharp edge and one serrated edge (52 teeth, 9 tpi). Blade is non-magnetic and non-sparking, made from hot rolled tungsten cobalt alloy (Haynes Alloy No. 25) with a parkerized non-reflective, light grey finish.
Inscription: 2-1/2 inch stainless steel (type 310). Cross-guard marked “U.S. NONMAGNETIC (with non-magnetic symbol); Serial No. ----/61 Imperial”. Later batches have an additional code number and no maker’s name.
Sheath: Made of grey plastic fibreglass and non ferrous alloy with webbing and two brass studded retaining loops. Sheath is marked: “U.S. NONMAGNETIC (with non-magnetic symbol) Imperial”. 1981 and 1983 contract scabbards are marked slightly differently.
Handle: 4-1/2 inch grey plastic fibreglass handle capped with a pinned stainless steel (type 310) pommel.
Remarks: This non-magnetic knife was issued to the U.S. Underwater Demolition Teams (UDT) and navy SEALS. Around 1,156 of these Imperial knives were ordered in 1961 at a cost of $99.67 each. Later batch quantities are very low by comparison. It is the rarest of the U.S. military issue knives.