Approved - knives withdrawn from private collections, checked, overhauled and certified by Coltelleria Collini

KNIFE WITHDRAWN FROM PRIVATE COLLECTION
* Origin: Withdrawn from a private collection, previously purchased
* Condition: Like new, never used and never removed from its original packaging
* Available on the market: Out of production
* Sharpness: Factory sharp
* Marks on blade: None
* Marks on handle: None
* Box: Present
* Sheath: Present
* Manuals, Certificates, and Warranties: Present
* Checked and Certified by our in-house laboratory

Intended use: Tactical/Sport

Type of production: Industrial
Country of production: Italy
Blade: N690Co stainless steel
Finish: Testudo burnishing
Handle: Forprene
Blade length: 128mm.
Blade thickness: 6.3mm.
Total length: 258mm.
Balance: rearward
Weight: 253g.
Sheath: Gen.1, ABS, with Tek-Lok multi-position attachment
Packaging: cardboard box with Extrema Ratio logos
Notes: from a private collection - 2007 model now out of production (replaced by the T4000 series)

KNIFE WITHDRAWN FROM PRIVATE COLLECTION
* Origin: Acquired from a private owner, previously purchased and used
* Condition: Overall good, with marks and scratches on the blade and guard. The sheath shows signs of wear.
* Commercial availability: Discontinued
* Edge: Original
* Box: Included
* Sheath: Included
* Manuals, Certificates, and Warranties: Included
* Inspected and Certified by our internal laboratory

The ExtremaRatio 39‑09 Operativo is a tactical collector's knife that combines the prestigious Italian military tradition with the precision of modern engineering. Inspired by the silhouette of the 1939 "paratrooper assault dagger", this model is built with premium materials and military-grade finishes that meet operational standards.

Its matte black coating, absence of flashy logos, and overall sturdiness make it ideal for discerning collectors, tactical blade enthusiasts, and those who value operational tools with strong symbolic meaning.

Every detail, from the Böhler N690 steel blade to the Forprene handle, is designed to ensure a balance of aesthetics, functionality, and reliability.

Intended use: collection / display / symbolic tactical use
Production type: high-end industrial manufacturing
Country of production: Italy
Blade: Böhler N690 steel, hardened (~ 58 HRC)
Blade finish: black oxide coating (MIL‑C‑13924 burnishing, non-reflective)
Handle: black Forprene
Blade length: 195 mm
Blade thickness: 6.3 mm
Total length: 319 mm
Weight: 338 g
Locking mechanism: fixed blade (not a folding knife)
Packaging: standard manufacturer box / rigid thigh sheath / nylon leg sheath

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.

KNIFE WITHDRAWN FROM PRIVATE COLLECTION
* Origin: Withdrawn from a private collection, previously purchased and used
* Condition: Overall in good condition, with superficial cosmetic marks on the blade due to actual use, which in no way compromise its functionality and use
* Available on the market: On the market
* Sharpening: Resharpened
* Marks on blade: Several superficial cosmetic marks on the burnishing
* Marks on handle: None
* Box: Present and complete
* Sheath: Present and in excellent condition
* Manuals, certificates, and warranties: Present
* Checked and certified by our in-house laboratory

Born from the growing demand of demanding professionals, Extrema Ratio presents ONTOS—a field knife designed to tackle any challenge. The name, derived from the Greek word for “the thing,” represents the perfect synthesis of strength, versatility, and reliability. Compact but extremely durable, ONTOS is the ideal companion in any situation, thanks to its partially serrated blade that always guarantees a sharp, ready-to-use cut.

Its nylon thigh sheath, equipped with the MOLLE system, is designed to remain firmly anchored even in the most difficult conditions, when the soldier is forced to give up his primary tactical equipment. And for those looking for an extra level of preparedness, a survival kit is available, sold separately, to be attached directly to the knife sheath.

Intended use: Heavy Utility

Type of production: Industrial
Country of production: Italy
Blade: N690Co 58HRC stainless steel
Surface treatment: MIL-C-13924 burnishing
Handle: Forprene
Blade length: 168mm.
Blade thickness: 6.3mm.
Total length: 299 mm.
Balance: advanced
Weight: 411 g.
Sheath: nylon thigh sheath, modular, compatible with M.O.L.L.E. systems.
Packaging: Cardboard box with Extrema Ratio logos
Notes: knife previously purchased and used, from a private collection

KNIFE WITHDRAWN FROM PRIVATE COLLECTION
* Origin: Withdrawn from a private collection, previously purchased and used
* Condition: Overall in excellent condition, with slight superficial signs of wear from use that do not compromise its functionality in any way. The sharpening stone and steel included have also been used, with minimal signs of cosmetic abrasion.
* Available on the market: Available on the market
* Sharpening: Factory sharpened, with minor “field” sharpening with the included ceramic stone
* Marks on blade: Minor surface wear from use
* Marks on handle: None
* Box: Present
* Sheath: Present
* Manuals, Certificates, and Warranties: Present
* Checked and certified by our in-house laboratory

The “Extrema Ratio Sethlans” is a fixed blade utility knife designed to handle a wide range of situations, suitable for survival, bushcraft, prepping, but also as a backup blade. The Sethlans is available in two versions with two different types of steel.

The Black version uses D2 steel, heat and cryogenically treated to 60 HRC, which has a high regrindability even with makeshift tools. To give greater hardness and resistance, the blade is coated with the new Teflon-based product “EXP DARK” offered by Extrema Ratio.

The knife comes with G10 scales featuring the ergonomic design characteristic of Extrema Ratio handles. They can be removed to reveal the skeletonized structure of the knife, which allows for maximum lightness with minimum thickness. For lovers of extreme customization, the full-tang structure allows the handle to be coated with paracord.

The sheath is made of a lightweight, minimalist Kydex. It can be disassembled and adapted for both left- and right-handed users. The addition of an optional belt clip allows the knife to be positioned either vertically or horizontally and makes the sheath much more versatile than the textile version. It also comes with a mini pouch with a M.O.L.L.E. system containing a double-sided sharpening stone and a firesteel for lighting fires.

Intended use: Survival, bushcraft, prepping

Type: Fixed blade
Blade length: 107mm
Total length: 224mm
Blade thickness: 6.3mm
Sharpening: Flat edge
Weight: 207g
Blade material: D2 steel (60HRC)
Blade finish: EXP DARK
Handle: G10
Notes: designed in collaboration with Daniele Dal Canto, Master Advanced F.I.S.S.S. instructor (Italian Federation of Survival Sports and Experiments).

KNIFE WITHDRAWN FROM PRIVATE COLLECTION
* Origin: Collected from a private individual, previously purchased and used.
* Condition: Overall in very good condition with a few minor cosmetic signs of use that do not affect its functionality
* Commercially available: Commercially available.
* Sharpening: Factory.
* Marks on blade: Small aesthetic marks from use.
* Marks on handle: A couple of small cosmetic marks. 
* Box: Present
* Scabbard: Present
* Manuals, Certificates and Warranties: Present
* Checked and Certified by our in-house laboratory

Satre is a small, lightweight and extremely durable fixed-blade knife. Given its characteristics, it finds use in a wide range of disciplines and uses ranging from survival activities, bushcraft or as an element of an EDC (Every Day Carry) kit.

It was designed in collaboration with Daniele Dal Canto, Master Advanced F.I.S.S. (Italian Federation of Sport and Experimental Survival) instructor.

In Neck Knife mode, through the use of a 550 paracord lanyard, it can be held around the neck while keeping the knife upright with the handle facing down. Metal eyelets on the sheath made of pre-shaped Kydex allow for the attachment of both the lanyard and accessory holder.

The full-tang skeletonized design, allows the knife to be customized using Paracord as a handle covering

The Black S600 version uses Böhler S600 steel. This steel is used in industrial manufacturing to make metalworking tools and in mold making.

Satre S600 is hardened and cryogenically treated, thus achieving an exceptional hardness of as much as 64 HRC. This gives it great wear resistance and the ability to guarantee a long edge cutting edge.

Intended Use: Neck Knife / Hiking / Utility

Type of production: industrial
Country of production: Italy
Blade: Bohler S600 64HRC carbon steel
Blade treatment:Black EXP DARK
Handle:carbon steel Bohler S600 64HRC
Blade length: 70mm.
Blade thickness: 5mm.
Total length: 163mm.
Weight: 78g.
Scabbard:Kydex, for neck
Packaging: cardboard box with Extrema Ratio logos.
Notes: previously purchased and used knife, withdrawn from a private collection - possibility to use the sheath with Ulti-Clip, M.O.L.L.E. or Tek-Lok systems (can be purchased separately)

WITHDRAWN FROM A PRIVATE COLLECTION

• Type: Previously Purchased
• Condition: In excellent condition
• Market Availability: First version with leather sheath
• Factory Sharpened: Yes
• Blade Marks: None
• Handle Marks: None
• Packaging: Complete, cardboard box with manufacturer logos
• Sheath: Leather
• Manuals, Certificates, and Warranties: Warranty certificates
• Checked and Certified: By our internal laboratory

Intended Use: Roasting

• Production Type: Industrial
• Blade Production: Italy
• Blade: N690Co stainless steel, hardened to 58HRC
• Blade Treatment: Satin finish
• Handle: Forprene
• Blade Length: 300mm
• Blade Thickness: 6.5mm at the handle, 4mm on the blade
• Total Length: 433mm
• Weight: 336g
• Sheath: Black leather
• Packaging: Cardboard box with Extrema Ratio logos
• Note: Also suitable as a sports or collectible knife

Extrema Ratio has applied its rigorous military standards to a series of professional kitchen knives.

The blade is made of tested BOHLER N690 steel, enriched with chromium, vanadium, molybdenum, and cobalt, hardened to 58HRC. The handle is made of Forprene, an elastomer that meets NATO standards for resistance to extreme conditions and is fully removable from the blade, allowing for thorough cleaning and maintenance.

Each knife comes with its own sheath, also derived from military equipment. While not designed to meet hygiene regulations, it ensures safe transport of the extremely sharp blade and protects it from impacts that could reduce its efficiency. We recommend using the sheath only for transportation and long-term storage.

KNIFE WITHDRAWN FROM PRIVATE COLLECTION
* Provenance: withdrawn from a private collection, previously purchased.
* Condition: New, never used, no original box
* Commercially available: Still in catalog, but now offered without “9th Col Moschin” logos on the blade
* Sharpening: Factory.
* Marks on blade: None
* Marks on handle: None
* Box: Absent
* Scabbard: Present, new
* Manuals, Certificates and Warranties: Present
* Checked and Certified by our in-house laboratory.

Commissioned and officially adopted in 2002 by the well-known 9th Incursor Rgt. “Col Moschin”, this model expresses the quintessence of the pure combat knife.

Inspired by the daggers with asymmetric blade and straight but oriented handle of the Arditi, from which the Regiment draws its vestiges, it has been reworked in a modern key. The center of gravity is strongly set back, the point particularly piercing. It is light, maneuverable and intuitive.

Every new raider gets one, every new raider is trained to use it to the fullest.

Intended use: Collector/Tactical/Military

Blade: N690Co 58HRC stainless steel with Desert Warfare finish
Handle: Forprene
Blade length: 160mm.
Blade thickness: 6.3mm.
Total length: 290mm.
Balance: set back, 1 cm. from the lower guard branch
Weight: 264g.
Sheath: Nylon, modular, thigh or belt, with removable inner plastic shell
Notes: previously purchased knife, from private collection

KNIFE WITHDRAWN FROM PRIVATE COLLECTION
* Provenance: withdrawn from a private collection, previously purchased.
* Condition: Overall in good condition.
* Commercially available: Still in catalog.
* Sharpening: Factory.
* Marks on blade: Marks and abrasions.
* Marks on handle: Small signs of wear and tear.
* Box: Present, not complete (absence of warranties and plastic bags).
* Scabbard: Present, in good condition.
* Manuals, Certificates and Warranties: - -
* Checked and Certified by our in-house laboratory.

Commissioned and officially adopted in 2002 by the renowned 9th Incursor Rgt. “Col Moschin,” this model expresses the quintessence of the pure combat knife. Inspired by the daggers with asymmetric blade and straight but oriented handle of the Arditi, from which the Regiment draws its vestiges, it has been reworked in a modern key. 

The center of gravity is strongly set back, the point particularly piercing. It is light, maneuverable and intuitive. Every new raider receives one, every new raider is trained to use it to the fullest.

Intended use: Collector/Tactical/Military

Blade: N690Co 58HRC stainless steel with Desert Warfare finish
Handle: Forprene
Blade length: 160mm.
Blade thickness: 6.3mm.
Total length: 290mm.
Balance: set back, 1 cm. from the lower guard branch
Weight: 264g.
Sheath: modular tactical, thigh or belt, Nylon
Notes: -

KNIFE WITHDRAWN FROM PRIVATE COLLECTION
* Provenance: withdrawn from a private collection, previously purchased.
* Condition: Overall in good condition
* Commercially available: Still in catalog.
* Sharpening: Factory.
* Marks on blade: Marks and abrasions.
* Marks on handle: Small signs of wear and tear.
* Box: Present, not complete (absence of warranties and plastic bags).
* Scabbard: Present, in good condition.
* Manuals, Certificates and Warranties: - -
* Checked and Certified by our in-house laboratory

Intended Use: Tactical/Military/Collection

Production type: Industrial
Country of Production: Italy
Blade: stainless steel N690Co 58HRC
Blade Treatment: Burnishing MIL-C-13924
Handle: Polymer
Blade Length: 167mm.
Blade thickness: 6.3mm.
Total length: 270mm.
Weight: 224g.
Sheath: Nylon thigh piece
Packaging: cardboard box with Extrema Ratio logos
Notes: Limited edition in 2018 pieces - Edition to celebrate 100 years of the Italian Ardites

KNIFE WITHDRAWN FROM A PRIVATE COLLECTION
* Origin: Withdrawn from a private individual, previously purchased
* Condition: USED
* Commercially available: available
* Sharpening: resharpened by our internal laboratory
* Signs on the blade: has superficial scratches on the entire blade on both sides of the blade (visible in the photos) which do not compromise the quality but only the aesthetics
* Signs on the handle: None
* Box: YES
* Sheath: Yes
* Manuals, Certificates and Guarantees: Yes
* Checked and Certified by our internal laboratory

The Giant Mamba has a tanto blade in Böhler N690 steel, 6.3 mm thick with a hardness of 58 HRC, flat edge and full-length lightening fuller.

The Forprene handle with threaded tang lock makes the knife solid and well-balanced. The sheath, M.O.L.L.E. compatible, is made of shock-absorbing nylon with a conical guide for quick insertion and extraction and a system that prevents shaking noises, it is equipped with a two-button safety flap, a thigh with anti-rotation rubber reinforcement and an ambidextrous reversible safety: simply pressing the trigger unlocks the blade.

Intended use: Tactical / Multi-role

Type of production: Industrial
Country of production: Italy
Blade: N690Co 58HRC stainless steel
Blade treatment: Mil-C-13924 burnishing
Handle: Forprene
Blade length: 163mm.
Blade thickness: 6.3mm.
Total length: 293mm.
Weight: 289g.
Sheath: Nylon
Packaging: Cardboard box with Extrema Ratio logos
Notes: -

KNIFE WITHDRAWN FROM PRIVATE COLLECTION
* Origin: Withdrawn from a private collection, previously purchased.
* Condition: Like new
* Commercially available: Discontinued, only made in 30 pieces
* Sharpening: Factory sharpened
* Marks on blade: None
* Marks on handle: None
* Box: Present
* Scabbard: Present
* Manuals, Certificates and Warranties: Present
* Checked and Certified by our in-house laboratory

Use: tactical, sporting, hiking, collection

Blade: integral, rolled Japanese stainless steel (San Mai) with 61.5HRC cryogenically hardened CoS cutting edge
Handle: forprene
Blade length: 90mm.
Blade thickness: 6.5mm.
Total length: 210mm.
Balance: set back 0.5cm. from the guard branch
Weight: 214g.
Sheath: ABS with multi-position Tek-Lok attachment
Notes:  new knife, withdrawn from private collections

KNIFE WITHDRAWN FROM PRIVATE COLLECTION
* Type: Previously Purchased - year of production 2004 - 1st series Shrapnel with double guard branch and kydex sheath
* Conditions: Like new
* Commercially available Yes
* Sharpening: Original
* Marks on blade: NO
* Signs on handle: NO
* Packaging: NO
* Sheath: In kydex
* Manuals, Certificates and Guarantees: YES
* Checked and Certified by our internal laboratory

Intended Use: Military/Tactical

Type of production: industrial
Blade production: Italy
Blade: N690Co 58/60HRC stainless steel
Blade treatment: MIL-C 13924 bluing
Handle: Forprene
Blade length: 110mm.
Blade thickness: 6.3mm.
Closed length: 142mm.
Total length: 210mm.
Weight: 210g.
Clips: absent
Sheath: ABS sheath with Tek-Lok attachment with automatic knife retention system.
Note: -

KNIFE WITHDRAWN FROM PRIVATE COLLECTION
* Origin: Collected from a private individual, previously purchased and used.
* Condition: Used, with obvious cosmetic signs of wear and tear, in no way compromising its use
* Commercially available: Discontinued, demilitarized version, without attachments and with top sharpening removed
* Sharpening: Factory (can be improved)
* Marks on blade: Various signs of wear, cosmetic in nature.
* Marks on handle: Various signs of wear, cosmetic in nature.
* Box: Present, original, complete
* Scabbard: Present, original, used, in good condition.
* Manuals, Certificates and Warranties: Present
* Checked and Certified by our in-house laboratory

Intended use: tactical/military/multi-role

Blade: full tang in N690Co 58HRC stainless steel with front upper portion of blade NOT sharpened
Handle: detachable in Forprene
Blade length: 180mm.
Blade thickness: 6.3mm.
Total length: 310mm.
Balance: advanced, 1.5cm from the lower guard branch
Weight: 378g.
Sheath: modular tactical with thread cutter, thigh or belt, Nylon - includes diamond sharpener and magnesium fire starter

Sheath: modular tactical with thread cutter, thigh or belt, Nylon - includes a diamond sharpener and magnesium fire starter