KNIFE FROM A PRIVATE COLLECTION
* Origin: Retrieved from a private collection, previously purchased
* Condition: Like new
* Available on the market: Discontinued
* Sharpening: Original
* Blade marks: None
* Handle marks: None
* Box: Included
* Sheath: Included
* Manuals, Certificates and Warranty: Included
* Inspected and Certified by our in-house lab

Japanese steel meets Italian excellence

For this 2020 collaboration, exclusively for Coltelleria Collini, we decided to offer a series of best sellers produced by Extrema Ratio. These knives are made using the renowned San Mai steel produced by Japan’s Takefu Steel. Specifically, we used carbon-rich V-Toku2 at 62/63HRC for the central core and stainless SUS410 for the outer layers, resulting in superior cutting performance, penetration, edge retention, ease of sharpening, and at the same time excellent corrosion resistance and increased resilience due to the laminated structure.

Model Col Moschin Compact: this First Production Run was limited to 15 numbered units, from 1 to 15.

The lethal efficiency of the COL MOSCHIN knife, now in compact version. Comes with a rigid belt sheath and BELT-CLIP. The sheath can be mounted horizontally, vertically, or at a 45° angle.

Usage: tactical, sports, hiking, collecting

Blade: full tang, laminated Japanese steel (San Mai) with cutting edge in V-Toku2 (carbon steel) at 62/63HRC and outer cheeks in SUS410 (stainless)
Handle: Forprene
Blade length: 110mm
Blade thickness: 6.5mm
Overall length: 212mm
Balance: 0.5cm behind the guard
Weight: 209g
Sheath: ABS with multi-position Tek-Lok attachment
Notes: Numbered edition - cardboard box with Extrema Ratio logos and certificate - as the cutting edge is carbon steel, it is recommended to lightly oil the blade to maintain its condition.

As in ancient Japanese Samurai swords.

The laminated steel – imported into Italy by Collini Steel directly from Japan’s Takefu Steel – is based on the age-old Japanese sword-making tradition. As early as the 1100s, Japanese blacksmiths were combining different metals to craft Katana swords with extraordinary cutting power, resistance, and flexibility. This revolutionary technique allowed Samurai swords to survive through centuries and become among the most fascinating human-made artifacts. Applied to modern metallurgy, this tradition now yields advanced steels already used in knife-making by brands like Fallkniven, Cold Steel, Mcusta, Kai, Sog, Zwilling, Rockstead, etc.

San Mai Steel Features: A combination of different metals bonded together to create a composite with amplified properties:

- Greater edge retention
Thanks to high-carbon premium steels (VG10, CoS, Shiro) or powder steels (SPG2) in the core, once hardened, the blade achieves cutting performance far superior to traditional steels.

- Higher resilience
Based on Japanese sword construction, the multi-layer steel is highly resistant to breaking due to the toughness of the core and flexibility of the stainless cladding.

- Improved corrosion resistance
The outer stainless layers ensure high corrosion resistance. Takefu’s multi-metal bonding also enhances galvanic protection of the edge.

- Easy processing post heat-treatment
Despite being hardened, the outer layers retain softness, allowing easy drilling, grinding, or welding. Cryogenic treatment is recommended for optimal performance.

- Enhanced aesthetics
Multi-layer or Damascus-patterned knives are elegant, refined, and highly valued by collectors worldwide.

For more information: collinisteel

Includes cover and article published in the October/November 2016 issue of "Coltelli" magazine.

Extrema Ratio – Made in Italy Tactical Excellence

Extrema Ratio is an international reference in professional tactical cutlery, official supplier to the Italian and French Armed Forces (NATO Code AD856). Every knife is designed for real operational use: selected materials, advanced treatments, and artisanal finishes guarantee robustness, precision, and reliability in all conditions.

Coltelleria Collini Guarantee: We have been a historic official Extrema Ratio dealer for over 25 years. We offer dedicated support, immediate availability, previews, and a catalog always updated with all the latest productions.

➡ Discover Extrema Ratio history, models, and news on our dedicated page