How to Use a Yotsuba Fillet Knife

A flexible fillet knife is not a short chef knife. The blade is meant to bend with the fish or follow a bone line, so you cut with light pressure and long strokes instead of a rock chop. Yotsuba puts a 7" flexible fillet in two rosewood bundles: the Utility + Fillet Pair and the 3PCS Set + 7" Fillet. Here's what the blade is for and how to run it.

What the 7-inch fillet is built for

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Yotsuba rates the same hardness band on the 5" utility that ships with either bundle (56+ HRC on the utility). The fillet is the specialty piece: fish, poultry and light boning where a stiff 8" chef would fight the curve of the bone.

Grip and board setup

1. Hold the handle with a pinch grip: thumb and forefinger on the blade spine just ahead of the bolster, the other fingers around the rosewood handle.
2. Keep a long, stable board. The tip travels farther than on a santoku, so a cramped board forces short, jagged cuts.
3. Wet fish skin is slippery. Dry the skin with a towel and keep a clean towel under the board if it walks on the counter.

Three strokes that matter

Skinning a fillet

Lay the fish skin-side down. Start at the tail, angle the edge just above the skin, and draw the blade toward the head while the off-hand holds the skin flat. Let the flex keep the edge against the skin instead of pressing the tip through the meat. If you hear tearing, flatten the angle.

Separating from the rib cage

For a whole side, run the tip along the rib bones with shallow passes. Flexible steel follows the curve; a stiff chef wants to jump the bone and leave meat behind. Work in short sections rather than one heroic pull.

Light boning

On chicken thighs or a small roast, use the tip to open a seam, then keep the edge against the bone while the handle hand guides. Stop when the cut turns into chopping. That job belongs to a chef or santoku, not this blade.

Which bundle has the fillet

• Utility + Fillet Pair: 5" utility (petty) plus the 7" fillet. Best when you already own a chef knife and mainly need detail prep and fish work.
• 3PCS Set + 7" Fillet: 8" chef, 7" santoku, 5" utility, plus the same 7" fillet. The three prep knives share high-carbon German stainless and about 14° edges; the fillet is rated HRC 56±2. Both halves of the bundle ship gift-boxed and may arrive separately.

If you are choosing between brisket, breaking and fillet shapes for smoked meat or butcher work, use the brisket, breaking or fillet checklist instead of this how-to.

Care that keeps the flex honest

• Hand wash with warm water and mild soap; dry with a soft towel right away.
• Skip the dishwasher and long soaks. Soft rosewood and a thin flexible edge both suffer.
• Hone lightly between fish days; when you sharpen, stay near the factory 14° per side. Our sharpening angle guide covers how to find that bevel.
• Store the fillet in its gift box or on a magnetic strip so the tip is not riding in a drawer with heavier knives.

For everyday lengths without a flexible fish blade, the Utility + 8" Chef Pair keeps both knives in stiff prep work. Wider set options sit on the knife sets page.

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