Two Opposing Layers of Titanium and Carbide-Diamond Sharpens as it Cuts!

RelentlessPerpetual Edge Fillet Knives, the world’s first knife that sharpens as you cut!

History of Cut

For centuries, bladesmiths focused on improving the blade’s rate of wear. By making the blade as hard as possible, the edge wears more slowly and stays sharp longer. However, making the blade harder also makes the edge more brittle and difficult to sharpen.

Inspired by Nature

The revolutionary Relentless™ Fillet Knife takes a completely different approach, it focused on the way the blade wears instead of the rate of wear resulting in a knife that can stay sharp for an entire season rather than for just a few fish. Relentless patented this Perpetual Edge™Technology which was inspired by the self-sharpening front teeth of the beaver. A beaver has really hard, iron-fortified enamel on the front side of its teeth and a relatively soft “dentin enamel” back side. This creates a differential in hardness between the front and the back which allows the softer dentin back side to wear more quickly relative to the harder iron-fortified front side, thereby leaving a thin, continuously razor-sharp edge, a perpetually lifelong edge that sharpens as it cuts.

Proven in Technology

In much the same way, the Relentless™ Fillet Knife blade is constructed of strong titanium on one side and an ultra-hard carbide and diamond “Power Strip” layer on the other side of the blade edge via spark-and-laser deposition which creates a differential hardness and acts like a beaver tooth that sharpens as it cuts and results in a perpetually-sharp edge that continually sharpens as you use it. This patented Perpetual Edge™ Technology is exclusive to Relentless and is unlike anything else on the market.

Relentless™ Knives feature a 100% aerospace-grade titanium blade. Titanium is extremely lightweight and extraordinarily strong which results in less wrist fatigue and enhanced durability. And since titanium is extremely resistant to corrosion and degradation, your Relentless knife will never rust, ever, not even in a saltwater environment.

New “Edge” Science

The carbide/diamond cutting edge on a Relentless™ Knife is micro-serrated, meaning it has tiny jagged, saw-like protrusions that function like thousands of micro-blades that further enhance the ability of the knife to cut soft, pliable things like fish meat which might otherwise squish (like a tomato). Also, one side of every Relentless™ Fillet Knife is treated with “SlickCut”, an anti-friction boron nitride compound which enhances the lubricity of the cutting edge to reduce friction and improve cutting performance.


Invariably, the first thing people notice about a Relentless™ Fillet Knife is the extreme gripping ability of its “True Grit” handle. The handle is made of glass reinforced ABS covered with the same gritty material used to create the non-slip surface found adjacent to swimming pools. This ensures you won’t lose your grip while filleting fish even if you have wet or slimy hands. The black True Grit surface is also “faceted” so that those facets scatter light in every direction and results in preventing the blade handle from ever getting hot, even if left in the hot sun. The handle’s “Expanding Oval Geometry” design tapers outward to the back to maximize hand-to-handle contact, preventing fatigue and slipping when gripping with either a firm or relaxed grip. This design allows you to choke up toward the front of the handle for more precise cutting while still maintaining a strong grip and accurate blade control.

“…this is the most significant advance in the art and science of cut that I have seen in over 55 years in the knife community.”

Ed Fowler, Blade Magazine Field Editor


Five Relentless Knife models:

10″ Straight – This is the knife preferred for flatter fish like halibut and salmon, for which it has to maneuver around the spine during cutting. MSRP $239.99

9″ Curved – Designed for bigger fish like large Mahi and other more significant fish. Allows for a single cut to slab out the side of a fish. MSRP $219.99

8″ Straight – Our version of the traditional straight-blade knife that is known for maneuverability around fish spines and gills. Ideal for Grouper and bottom fish with stout, complex spines. MSRP $219.99

7″ Curved – Ideal for the coastal fisherman for cleaning larger Mahi, Snapper and the like. Also, for the freshwater fisherman who prefers a larger knife. MSRP $209.99

6″ Curved – Designed for the freshwater fisherman and inshore saltwater fisherman. Also a good knife for cutting bait. MSRP $209.99

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