Extrema Ratio - Extrema Ratio Ultramarine diving knife with hole

The Ultramarine is the result of 4 years of development by the company in collaboration with military diving teams and special forces to construct an extremely versatile knife. It is suitable for combat situations in the field and for combat situations under water, as a rescue knife in emergency situations, as a survival knife or as a tool in special operations. The blade is specially made for use under water and can withstand high pressure without breaking. On one side, the blade is ground continuously and tapers towards the front like a dagger. On the other side, the blade has a serrated edge and has a shackle opener. Another special feature of this knife is the hole in the middle of the blade, which reduces water resistance.

- Weight: 380g
- Blade length: 140 mm
- Total length: 296 mm
- Blade thickness: 6.3 mm
- Blade material: Böhler steel N690 (58HRC)
- Handle material: nylon
- Serrated edge: yes
- Blade grind: flat grind
- Blade finish: Burnishing MIL-C-13924

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