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ExtremaRatio - Shrapnel OG Satin in San Mai CoS - knife

92 % of 100
Fuori Produzione / Discontinued

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For this new exclusive collaboration with Extrema Ratio we decided to propose a best seller in the world of cutlery, the Shrapnel model. It's a satin blade version but the most important thing is that has been used, for the first time in Italy, the famous Japanese Steel San Mai produced by Takefu Steel. Specifically, we used the CoS (Cobalt Special, considered mechanically superior by 25% compared to the already appreciated VG10) for the central plate and the 420J2 (55 HRC) for the two side plates, in order to have a high cutting capacity, but at the the same time a remarkable resilience and resistance to oxidation.

A First Production Run of 30 pieces has been made.

SHRAPNEL OG is a truly versatile “back up” knife with marked combat qualities. Its leaf-shaped blade is flat ground at a characteristically low angle to a wide, extraordinarily sharp edge. The included hard sheath can be worn vertically, horizontally or obliquely (at a 45° angle). Tthe SHRAPNEL OG hilt design does not include a guard.

Use: tactical , sports , hiking , collection
Blade: Full , Japanese- rolled stainless steel ( San Mai) with sharp CoS to 61,7HRC in cryogenic tempering
Handle: Forprene
Blade length: 90mm.
Blade Thickness: 6.5 mm.
Overall length: 210mm.
Balancing: back to 0.5cm . by guard branch
Weight: 214g.
Sheath: ABS with Tek - Lok multi attack
Notes: cardboard box with Extremaratio logos and certificate

Clad Metal
It is a composite metal partly or entirely diffusion bonded together of different kinds of metals.

Metal composition shows higher performance which respective materials alone do not possess and the performance complements opposite characteristics of each material, that is "compound characteristics"

Clad Effect on Cutleries

Like Japanese swords, clad metal is hard to break or bend, thanks to the toughness as the hard steel part is clad with soft steels.
Easy to work on
Cladded structure is easy to apply on such works as forging, grinding, sharpening or polishing to make a sharp blade.

Improved corrosion resistance
Proper material combination generates electrical potential difference and it enhances the corrosion resistance on blade edge.

Better and long lasting sharpness
Steel after forging pressure makes the microscopic structure denser and improves the sharpness and ensures long lasting performance.

Resource saving
As high class steel is used only for necessary part, it is perfectly cost effective..

Easy distortion correction
As the steel is bonded with soft steel materials, its blade is hard to break and the distortion correction is easy.

Easy drilling and welding after heat treatment
Though the steel gets harder after heat treatment, the soft steel never loses its softness, enabling the material to be drilled or welded.

Design improvement
Laminated patterns or Damascus patterns appear from basis materials which are bonded with different kinds of metals.



Company profile:
Extrema Ratio is specialized in the development and manufacture of professional knives expecially for Military, Public Safety and Rescue.

The level of production is high, the philosophy of the brand is to produce technical equipment of great functional value, long service life, serial consistent quality at reasonable cost to the public authorities and institutional customers. In other words, a top-quality product at competitive prices.

The production is characterized by industrial and handmade finishing process, feature that has a strong identity to the company: are automated and industrialized only the processes that guarantee uniformity, high production capacity and economies of scale, remain artisanal processes, such as checks, guarantee the reliability and high overall quality of the individual pieces within the series, as well as operations, which by their very nature, derive their functionality from the user's manual features such as flat sharpening, which are carried out and all exclusively by hand.

Thanks to the interaction with the Armed Forces, Italian and international, the company has collected and continues to accumulate valuable experience and information that allow it to proceed with the development of truly qualified and professional knives.

"We manufactured to specifications or we develop new products to solve problems that the customer indicates."

The company's success is that it has worked with the Armed Forces with the intention, successfully achieved, to raise quality and functional standards of the modern military knives.

The high level of quality is given by the design's function, from the choice of the best materials and the latest treatments.

The company carries out internal tests of effectiveness and durability of the products through the development of specific instruments.

With the collaboration of the Faculty of Kinesiology, University of Perugia who oversaw the ergonomics of its products: the essential skills of the same interface with the user.

With the collaboration of the Faculty of Engineering, University of Florence who care tests and analysis of structures, materials and surface finishes of the product. The production potential is sufficient to ensure governmental supplies on a large scale, with very high quality standards.

The company is certified ISO 9001 and is registered among the suppliers of the Armed Forces, NATO code (N / CAGE): AD856.

Extrema Ratio is the official supplier of the Italian and French Armed Forces, as well as actively cooperates and is a supplier of the best Italian units and some of the best military units and public safety companies around the world.



More Information
BrandExtrema Ratio
Country of productionItaly
Blade TypeFixed
Blade Length11/12cm
Blade TipSpear point
Blade thickness6,5 mm
Blade FinishNone (Satin / Stonewashed)
Stainless SteelCoS (laminated)
Handle MaterialSynthetic
RarityVery Rare
Materials and Finishes8
Steel Quality8,5
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