The Marttiini Superflex Filleting Knife 15 is a classic Finnish fillet knife reimagined for even greater precision. The defining feature is the blade — at 6 inches, it is engineered to be exceptionally flexible, bending dramatically under pressure to hug the contour of a fish and follow bones cleanly without tearing the flesh. That flexibility is what separates a true fillet knife from a general-purpose blade, and the Superflex takes it further than most.

The stainless steel blade resists corrosion and cleans up easily — an important quality for a knife that will spend time around water, fish, and damp hands. This blade length is ideally suited for pan-sized fish in the range of about 2 pounds — think perch, trout, walleye, or similar species.

The handle is shaped from thermally treated Finnish birch — a process where the wood is heat-cured without chemicals, deepening its color to a warm brown and significantly improving its resistance to moisture. A laser-etched crosshatch texture covers the grip zone, giving the handle a sure, non-slip feel even with wet hands during a long cleaning session. A brass ferrule transitions cleanly from handle to blade.

The knife comes with a brown leather sheath with embossed detailing — built for the tackle box, the dock, or the cleaning table.

• Brand: Marttiini
• Country: Designed in Finland, Made in Estonia
• Total Length: 10.6" (27 cm)
• Length of Blade: 6" (15 cm)
• Blade Material: Stainless Steel
• Handle Material: Heat Treated Waxed Birch
• Sheath Material: Brown Leather