- Ferrum E Tactical Mud Aluminium, Satin, a small, strongly built EDC folding knife from Extrema Ratio. Proven solutions from the company, profiled anticordal aluminium handle, proven N690 steel for the blade, Ball bearings for a smooth opening!

This product is intended for use only by adults with knowledge and experience in handling sharp cutting tools. Improper use of the knife can result in serious injuries. The blade is extremely sharp and can easily cut through skin and tissue; therefore, extra caution should always be exercised while cutting, and hands should be kept away from the cutting edge. To prevent the knife from slipping, it is recommended to cut on a stable, non-slip surface and avoid excessive force, which may cause uncontrolled blade movement.
Leaving the knife on the edge of a table, countertop, or in easily accessible places—especially where children are present—poses a significant safety risk. The knife should always be properly secured after use, ideally by placing it on a stable surface or storing it in designated knife blocks, protective sheaths, or magnetic strips. The knife should never be used for tasks it is not designed for, such as opening cans or prying objects, as this can damage the tool and lead to dangerous accidents.
A dull blade increases the risk of injury, as it requires more force and is more likely to slip from the material being cut. Therefore, it is essential to sharpen the knife regularly to maintain optimal sharpness. Additionally, proper cleaning and drying of the knife are necessary to prevent corrosion and bacterial growth. Periodic inspection of the handle and blade is recommended to check for cracks, chips, or looseness. If any damage is detected, the knife should be repaired or replaced immediately.
When using the knife, focus solely on the task at hand—avoid talking on the phone, watching television, or other distractions while cutting. Ensure proper lighting in the workspace for better visibility and control. Please note that some countries or regions have laws restricting the ownership and carrying of knives. Before purchasing or using this knife, verify that its use is legal in your location according to applicable regulations.
Following these safety guidelines will help ensure safe and effective knife use, minimizing the risk of accidents and extending the lifespan of the tool.
Ferrum E Tactical Mud Aluminium, Satin (EDC) strongly built folding knife from Extrema Ratio. Proven solutions from the ER, profiled aluminium handle, proven N690 steel for the blade, Ball bearings for a smooth opening! Perfect for everyday carry, a reliable companion for everyday life.
N690 - cobalt-rich 1.65% (Co) corrosion-resistant, high-carbon 1.07% (C) martensitic chromium steel 17.30% (Cr) with molybdenum 1.10% (Mo), vanadium 0.10% (V). Developed to provide better wear resistance compared to the original Böhler N690 steel, but with a higher cobalt (Co) content in its composition. It is characterised by extremely high corrosion resistance and long edge retention. One of the best tool steels in the world today. Hardened to between 58 and 61 HRC. Manufactured by Böhler Edelstahl in Kapfenberg, Austria.
Blade - Drop point type finished with an elegant satin finish. The small thickness of the blade combined with the high flat grind (Flat Grind) gives excellent cutting edge geometry and extreme cutting performance. Ball bearings support the opening of the blade with a quick flipper (index-finger flipper) when opened acting as a stag. The entire blade is locked with the proven and popular liner lock.
Handle - anticordal anodised aluminium grips, screwed to a steel frame. The chamfered edges of the covers eliminate sharp edges and the finger recesses characteristic of Extrema Ratio improve grip security. The so-called open-backed construction without the typical backspacer, secured to each other by steel spacer sleeves, facilitates cleaning. The simple, robust construction provides the assurance of many years of use. The two-position (right/left) steel deep-carry clip allows you to carry the knife discreetly in your pocket in the tip-up position (blade tip up).
Technical data:
Product number: 04.1000.0366/SAT/TM
Product name: Ferrum E (EDC) Tactical Mud Aluminium, Satin,
Overall length: 186.0 mm / 7.32"
Blade length: 75.0 mm / 2.95"
Blade thickness: 3.0 mm / 0.12"
Handle length: n.d.
Handle thickness: n.d.
Weight: 87.0 g / 3.06 oz
Blade material: N690
Blade hardness: 58 HRC
Blade grind: Flat
Blade finish: Satin
Handle material: Anticordal Anodized Aluminium
Handle finish color: Tactical Mud
Backspacer material: Stainless Steel
Backspacer colour: n.d.
Clip: Right / Left, Tip-Up
Clip material: Stainless Steel
Pivot mechanism: Ball bearing
Locking mechanism: Liner Lock
Opening method: Manual, flipper
Additional accessories: None
Designer: Extrema Ratio
Brand name: Extrema Ratio
Manufacturer: Extrema Ratio, Italy
Country of origin: Italy
Design: Sharg® company