- Dobermann IV S600 Black Forprene, EXP Dark the most versatile Extrema Ratio knife. It is perfect for hunting outdoor activities, defense up to unrestricted military use. Blade with Drop Point profile.

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.
Dobermann IV S600 Black Forprene, EXP Dark, the knife has undergone significant design changes over the years to meet the ever-changing needs of users, while maintaining consistency with the original K1 Dobermann design , the first ER knife from 1997. Also, its latest IV version stands out for its outstanding durability and structural toughness. It is arguably Extrema Ratio's most versatile knife. It performs perfectly during hunting, survival activities, up to unlimited military use.
S600 - a type of steel you don't often come across! High speed steel with high molybdenum, tungsten and good vanadium content, providing excellent hardness, wear resistance and strength properties. The presence of cobalt promotes the formation of small, evenly spaced carbides for increased wear resistance. S600 is hardened and cryogenically treated to achieve an exceptional hardness of 64 HRC. This gives high wear resistance and retains sharpness well. Manufactured at the Böhler-Uddeholm steelworks in Austria .
Blade - solid 6.3 mm thick with a long false blade. Drop point type blade with a wave-shaped edge (Revurve) providing above-average cutting properties, used in good tactical, survival, hunting knives, among others. Made from Böhler S600 molybdenum high-speed steel with 4.5% chromium content, which makes it an oxidizable steel. For this reason, Extrema Ratio has chosen a new blade coating - EXP DARK - on which it has immortalized the name of the S600 steel , its exceptional hardness of 64 HRC and information on Cryogenic treatment - all features that highlight the uniqueness of this alloy. Plain blade was derived with a high flat grind (Flat grind ). Projecting beyond the outline of the Handle, the blade forms a guard that prevents the hand from slipping on the blade while working.
Handle - covered with non-slip textured grips with rubber-like properties. Made of Forprene thermoplastic elastomer (flexible return, softness, resistance to chemicals), guarantees a firm grip even with wet hands. Textured thumb ramp on the back of the Handle. Steel head with an enlarged hole (lanyard hole) for pulling a lanyard or safety line, can act as a hammer / glass breaker and more.
Sheath - tactical, made of Cordura, equipped with an attachment system for the M.O.L.L.E. Adapted for both left-handed and right-handed users.
Technical data:
Product number: 04.1000.0184/S6/BLK
Product name: Dobermann IV S600 Black Forprene, EXP Dark
Overall length: 316.0 mm / 12.4”
Blade length: 185.0 mm / 7.28”
Blade thickness: 6.3 mm / 0.25”
Handle length: n.d.
Handle thickness: n.d.
Weight: 377.5 g / 13.3 oz
Blade material: Böhler S600
Blade hardness: 64 HRC
Blade grind: Flat
Blade finish: EXP Dark coating
Handle material: Forprene
Handle finish color: Black
Sheath (holster): Cordura
Additional accessories: None
Designer: Extrema Ratio
Brand: Extrema Ratio
Manufacturer: Extrema Ratio, Italy
Country of origin: Italy
Developed by: the Sharg® company