Extrema Ratio

This line of knives fits between the Basic Folders series and the Heavy Folders series. The typical mechanism of the series is the LINER-LOCK. The overall structure is robust. All knives in the MF series have a rear glass breaker. They also feature the innovation of the adjusting locknut on the blade fixing pivot.

By removing the locknut it is possible to tighten or loosen the central pivot as desired, to achieve the desired opening fluidity. It will be enough to lock the pivot screw with the locknut to fix the adjustment. The hemispherical milling on the handles facilitate the change of grip from "saber grip" to "reverse grip". The clip is reversible.

The BC (Belt Cutter) version features a rear seatbelt cutter with an easily obtainable and replaceable industrial cutter blade. In addition, a slotted screwdriver is inserted inside the handle that allows for the adjustment and calibration of firearm optics. This version is produced with a rough grip to offer a better grip.

Intended use: Tactical

Type of production: Industrial
Blade production: Italy
Blade: Stainless steel N690Co 58HRC
Blade treatment: Testudo
Handle: Anticorodal
Blade length: 95mm.
Blade thickness: 4mm.
Closed length: 134mm.
Total length: 225mm.
Thickness when closed: 24mm.
Balance: -
Weight: 165g.
Closure: Liner Lock
Clip: Stainless Steel
Sheath: -
Packaging: Black cardboard box with Extrema Ratio logos
Notes: -

Knife withdrawn from private collection. Very rare model made by Extrema Ratio with Borut Kincl ( Slovenian martial arts master and trainer of police and military special forces) no longer in production since 2009 - Overall in very good condition. Complete with cardboard box. Checked and certified by our in-house laboratory Coltelleria Collini.

Intended use: tactical/military

Type of production: industrial
Blade: stainless steel N690Co 58HRC
Blade Production: Italy
Handle: PVD
Blade length: 95mm.
Blade thickness: 3mm.
Length closed: 140mm.
Total length: 235mm.
Balance: -
Weight: 195g.
Closure: Liner Lock
Clip: reversible and removable stainless steel
Sheath: -
Notes: safety catch when knife is open

Translated with www.DeepL.com/Translator (free version)

Japanese steel merges with Italian excellence

For this 2019/2020 collaboration, exclusive to Collini Cutlery, we have decided to offer a series of best sellers produced by Extrema Ratio. Knives made with the famous San Mai steel produced by the Japanese Takefu Steel. Specifically, for the central sheet we used the carbonaceous V-Toku2 at 62 / 63HRC and the stainless SUS410 for the two external sheets, in order to guarantee a very high cutting, penetration and sealing capacity of the wire together with an ease of regrinding and maintenance but at the same time the blade has a remarkable resistance to corrosion and an important increase in resilience given by the type of foreign steel and the laminated structure.

FULCRUM C model: for this First Production Run, a circulation of 10 pieces numbered from 1 to 10 was produced.

FULCRUM C is the compact version of FULCRUM, it maintains all the characteristics of solidity and robustness and, thanks to the reduced dimensions of the blade (only 110 mm) and the handle, it is easily portable and concealable. The rigid sheath can be positioned horizontally, vertically or in a 45 ° inclined position. The only safety of the sheath is automatic with extraction and re-insertion by pressure, this detail makes it an intuitive and extremely fast tool, particularly suitable for emergency use and for personal defense.

Use: backup knife
Blade: integral, in Japanese laminated steel (San Mai) with cutting edge in V-Toku2 (carbon) at 62 / 63HRC and external cheeks in SUS410 (stainless steel)
Blade thickness: 6.3 mm.
Blade length: 90 mm.
Total length: 210 mm.
Balancing: set back to 0.5cm. from the guard branch
Weight: 210g.
Sheath: ABS with Tek-Lok multiposition attachment
Notes: Numbered edition - cardboard box with Extremaratio logos and certificate

As in the ancient swords of the Japanese Samurai.

Rolled steel - imported into Italy from Collini Steel directly from the Japanese Takefu Steel - is based on the ancient Japanese tradition in the creation of the famous Samurai swords. Already in 1100 the expert Japanese blacksmiths in fact combined different materials to give the Katana swords incredible cutting capabilities combined with a resistance and flexibility previously unknown. It is thanks to this revolutionary construction technique that the swords from Samurai have been preserved to the present day becoming one of the most fascinating objects made by man. Following this tradition applied to modern metallurgy, we are now able to have technologically advanced steels already tested and used in cutlery also by famous brands such as Fallkniven, Cold Steel, Mcusta, Kai, Sog, Zwilling, Rockstead, etc.

Characteristics of San Mai steel: These are different types of metals bonded together to create a composite that encloses and intensifies the strengths of the metals taken individually:

- Longer tool life
thanks to the use of high quality steel with a high carbon content (V-Toku2, VG10, CoS, Shiro) or sintered (SPG2), in the heart of the sheet (Core Steel), the blade once hardened, reaches hardness and cutting performance significantly higher than that achieved with the use of traditional steels.

- Greater resilience
built with the principle of Japanese swords, multilayer steel is difficult to break thanks to the toughness of the central steel (Core Steel) and the elasticity of the steel used for the lateral coating (Stainless Steel).

- Better corrosion resistance
the steel used for the external layers (Stainless Steel) guarantees the blade a high resistance to corrosion. The combination of the two or more materials used by Takefu Steel generates, at the galvanic level, a structure that improves the corrosion resistance also on the wire.

- Easy processing even after heat treatment
although normally the steel becomes harder after hardening, the lateral steel used in multi-layer processing does not lose its softness and allows easy processing, drilling or welding even after heat treatment. For optimum performance of the blade, cryogenic treatment is recommended.

- Improvement of the aesthetic result
The knives made with multistate steel or with damask pattern at the end of the processing are aesthetically elegant, refined and highly appreciated by collectors all over the world.

Helmsman is a knife designed and perfected in every single detail for its primary use in a nautical environment and represents the evolution of the BF2 V model presented on the Amerigo Vespucci School Ship in 2013 and dedicated to the most beautiful ship in the world.

The blade, which reaches a length of 87 mm, has a serration at the base while the tip has a flat grinding that allows symmetrical cutting work with wider support while the stone washed finishing process preserves more from corrosion in a marine environment.

Intended use: Sports / Tactical / For Sailing Boat

Type of production: industrial
Blade: N690Co 58HRC stainless steel with Stone Washed finish
Country of production: Italy
Handle: Anticorodal with stainless steel reinforcements
Blade length: 87mm.
Blade thickness: 3mm.
Length closed: 124mm.
Total length: 210mm.
Weight: 143g.
Closure: Liner Lock
Clip: reversible and removable in stainless steel
Notes: ankle band / loose knots - small shackle - Tactical quick release hanger - Safety catch with open knife - Safety ankle fastener / Knot release

The BF2 R is a full size lock knife particularly suitable for professional use by military and police operators. The model retains all the features of the BF2, upgraded with the new high speed Razor opening opening system.

Target: Tactical / Military

Type of production: industrial
Blade: stainless steel N690Co 58HRC
Country of production: Italy
Handle: Anticorodal
Blade Length: 90mm.
Blade thickness: 3mm.
Closed length: 130mm.
Total length: 214mm.
Weight: 140g.
Closure: Liner Lock
Clip: deep pocket, reversible and removable, in stainless steel
Sheath: -
Notes: Additional safety catch with open knife

The BF2 R is a full size lock knife particularly suitable for professional use by military and police operators. The model retains all the features of the BF2, upgraded with the new high speed Razor opening opening system.

Target: Tactical / Military

Type of production: industrial
Blade: stainless steel N690Co 58HRC
Country of production: Italy
Handle: Anticorodal
Blade Length: 90mm.
Blade thickness: 3mm.
Closed length: 130mm.
Total length: 214mm.
Weight: 140g.
Closure: Liner Lock
Clip: deep pocket, reversible and removable, in stainless steel
Sheath: -
Notes: Additional safety catch with open knife

This folding knife is projected for those who are looking for sturdiness and reliability of a fixed blade but also for compact sizes. Its N690 steel blade is available with Drop or Tanto point. For standard use the well known liner lock is enough safe. In case of hard extreme works it is requested to insert the steel pin in the proper hole to cross the handle and the blade, obtaining in this way a sturdy and reliable knife as much as a fixed blade. The steel clip can be removed or even placed on the opposite site of the handle by replacing it with the second supplied clip

Intended use: Tactical / Heavy Folder

type of production: Industrial
Country of production: Italy
Blade: Stainless steel 58HRC N690Co
Blade treatment: Testudo MIL-C-13924
Handle: Anticorodal
Blade length: 91mm.
Blade thickness: 5.6mm.
Closed Length: 149mm.
Overall length: 240mm.
Thick when closed: -
Weight: 271g.
Lock: Liner Lock system with additional safety latch and screw
Clip: Stainless Steel
Packaging: cardboard box with Extrema Ratio logos

This folding knife is projected for those who are looking for sturdiness and reliability of a fixed blade but also for compact sizes. Its N690 steel blade is available with Drop or Tanto point. For standard use the well known liner lock is enough safe. In case of hard extreme works it is requested to insert the steel pin in the proper hole to cross the handle and the blade, obtaining in this way a sturdy and reliable knife as much as a fixed blade. The steel clip can be removed or even placed on the opposite site of the handle by replacing it with the second supplied clip

Intended use: Tactical / Heavy Folder

type of production: Industrial
Country of production: Italy
Blade: Stainless steel 58HRC N690Co
Blade treatment: Testudo MIL-C-13924
Handle: Anticorodal
Blade length: 91mm.
Blade thickness: 5.6mm.
Closed Length: 149mm.
Overall length: 240mm.
Thick when closed: -
Weight: 271g.
Lock: Liner Lock system with additional safety latch and screw
Clip: Stainless Steel
Packaging: cardboard box with Extrema Ratio logos

Extrema Ratio - Panther Designed Borut Kincl - knife
Knife collaboration between Extrema Ratio and Borut Kincl trainer official special forces Slovenes "ESD"
Intended use: Tactical / Military
Type of production: industry
Blade: stainless steel N690Co 58HRC
Production Lama: Italy
Handle: Anticorodal
Blade length: 95mm.
Blade Thickness: 3mm.
Length closed: 140mm.
Overall length: 235mm.
Balancing: -
Weight: 210g.
Lock: Liner Lock
Clip: reversible and removable stainless steel
Sheath: -
Notes: safety locks to open knife

This knife is a Collini Cutlery exclusive edition, the one and only Karambit blade ever made by Extrema Ratio and you will not be able to find it in other stores - This is a very small worldwide limited edition of 50 serialized pieces.

Blade: 58HRC N690Co Testudo Stainless Steel
Country of production: Italy
Handles: Black satin anticorodal
Blade Lenght: 90mm.
Blade Thinckness: 4mm.
Total Lenght: 205mm.
Hole Diameter: 22mm
Weight: 152g.
Sheath: Kydex with Tek-Lok
Notes: Worldwide limited edition, only 50pcs each serialized

ExtremaRatio - SKAR - Karambit Collector's Edition - knife

SKAR COLLECTOR'S EDITION

Available in only 10 numbered copies (from 1 to 5 in the version black blade and 1 to 5 in the blade clear version), this edition of the Skar Extremaratio is sold in an elegant box in polymers with the version Skar training aluminum.

Intended Use: collection / CQB

Type of production: Industrial, Limited
Blade: stainless steel N690
Treatment Blade: Stonewashed
Production Lama: Italy
Handle: Anticorodal removable grips
Blade length: 90mm.
Blade Thickness: 4mm.
Overall length: 205mm.
Hole diameter: 22mm
Balancing: back, 2 cm from the branch guard
Weight: 152g.
Sheath: Kydex, thermoformed, connection type Tek-Lok
Notes: Limited edition and numbered with certificate, in only 5 pieces
Housing: plastic, with logos ExtremaRatio

Faithful implementation of the 1/1 scale SKAR. Entirely anodized aircraft aluminum, this Karambit is made by Extrema Ratio in collaboration with Cutlery Collini Busto Arsizio.

Free tip and sharp, this knife offers a realistic feeling and maximum safety during training and practice of martial arts that require the use karambit.

Intended Use: Training
Production: Italy
Lama: Aeronautical Aluminum 6061 T6
Treatment: Anodizing
Handle: series comes the paracord to assemble; select the drop down menu under the favorite color! E 'can also purchase the handle in aluminum that are mounted on steel version SKAR.
Blade length: 90mm.
Blade Thickness: 4mm.
Overall length: 205mm.
Hole diameter: 22mm
Weight: 34g.

This knife is a Collini Cutlery exclusive edition, the one and only Karambit blade ever made by Extrema Ratio and you will not be able to find it in other stores - This is a very small worldwide limited edition of 50 serialized pieces.

Blade: 58HRC N690Co Testudo Stainless Steel
Country of production: Italy
Handles: Black satin anticorodal
Blade Lenght: 90mm.
Blade Thinckness: 4mm.
Total Lenght: 205mm.
Hole Diameter: 22mm
Weight: 152g.
Sheath: Kydex with Tek-Lok
Notes: Worldwide limited edition, only 50pcs each serialized

This knife is a Collini Cutlery exclusive edition, the one and only Karambit blade ever made by Extrema Ratio and you will not be able to find it in other stores - This is a very small worldwide limited edition of 50 serialized pieces.

Blade: 58HRC N690Co Stonewashed Stainless Steel
Country of production: Italy
Handles: Black satin anticorodal
Blade Lenght: 90mm.
Blade Thinckness: 4mm.
Total Lenght: 205mm.
Hole Diameter: 22mm
Weight: 152g.
Sheath: Kydex with Tek-Lok
Notes: Worldwide limited edition, only 50pcs each serialized

Extrema Ratio is pleased to introduce the new Police III.

This folding is equipped with:
* Standard blade, made with special squared shape
* Lama emergency (belt cutter) with a flip-
* Sciogli node with particular safety lock
* Evacuation hammer
* Clip for pocket port
* Synthetic sheath

TECHNICAL DATA

* Overall Length: 220mm.
* Blade length: 86mm.
* Weight: 258g.
* Blade Thickness: 3mm.
* Steel Blade: 58HRC N690Co

Intended Use: Tactical/Military

Type of production: industrial
Blade: stainless steel N690Co 58HRC
Country of Production: Italy
Handle: Anticorodal
Blade length: 90mm.
Blade thickness: 3mm.
Length closed: 124mm.
Total length: 210mm.
Weight: 140g.
Closure: Liner Lock
Clip: reversible and removable stainless steel
Notes: additional safety catch when knife is open

Intended use: tactical / military / backup

Blade: stainless steel N690Co 58HRC
Handle: Anticorodal 4.5mm thick
Blade length: 95mm.
Blade thickness: 6mm.
Length closed: 127
Total length: 220mm.
Balancing: -
Weight: 200g.
Closure: Back Lock
Clip: removable and reversible in stainless steel
Sheath: -

Intended use: tactical / military / backup

Blade: Stainless Steel N690Co 58HRC Desert Warfare
Manicure: 4.5mm Thickness Anticorodal
Blade Length: 95mm.
Blade thickness: 6mm.
Closed length: 127
Total length: 220mm.
Balance: -
Weight: 200g.
Closing: Back Lock
Clip: Removable and reversible in stainless steel
Sheath: -
Notes: safety mechanism both in opening and closing

Directly derived from military specifications, this fold has been developed to replace a fixed blade in use.

To achieve this result, very strong materials, high thicknesses and a solid and safe opening and closing system were used: the back lock.
The knife is equipped with a manual safety device which confers maximum safety in use and reduces the risk of accidental closure in manieradrastica.
The safety device, if inserted in closing, prevents the knife from being turned against itself in the case of subtraction.

Materials and workmanship:

All parts of the knife are machined from high-precision CNC machines, while assembly, adjustment and sharpening are carried out by hand.
The blade is made of cobalt N690 stainless steel, a steel with very high resistance to mechanical stress, cutting capacity, thread strength and corrosion resistance. The grinding is flat and the hardness is 58HRC.
The grips of the handle are in Anticorodal, an aluminum alega with high resistance to mechanical stress and oxidation.
The tang, in hardened N690, is an effective emergency crystals. All screws, pins and clips are in burnished stainless steel. The blade, the lever and the shank are covered with Testudo treatment, very resistant to abrasion and oxidation. The cheeks are black anodized.

Intended use: tactical / military / backup

Blade: stainless steel N690Co 58HRC
Handle: Anticorodal thickness 4.5mm
Blade length: 95mm.
Blade thickness: 6mm.
Length closed: 127
Total length: 220mm.
Weight: 200g.
Closure: Back Lock
Clip: removable and reversible in stainless steel
Notes: safety mechanism both in opening and closing