When It comes to professional fillet knives, no one product these knives better than the Japanese. The best Japanese fillet knife is commonly referred to as “Deba”. This is also the type of knife that I have been use to fillet fish for many years as Deba knives are usually thicker, sharper and stronger than traditional western fish fillet knives.
You can visit link for more type of Japanese knives, but for me Deba Japanese fillet knife is perfect for makings ultra-thin slices of fish and filleting whole fish due to its wide and long shape. Under proper maintenance, these knives can make a sharp and perfect tool for cutting fish, vegetable, chicken and meat.
Here is the website contains some good content about fillet knife.
Mercer Culinary Asian Collection Deba Knife is an excellent knife for making paper-thin slices. Due to its 6 inches blade, this knife can fillet most medium size fish, vegetables and meat.
It is NSF certified for the blade quality, which will guarantee that the blade achieves all the standards for safety, durability, and performance.
You can expect that the blade of Mercer Culinary is reliable enough for both home use and commercial purpose and still offers the great performance. It features the non-slip Santoprene handle, which provide you comfy grip and perfectly balanced.
What I like most about this knife is that it is made of premium German steel material. This stainless-steel material makes the knife discoloration, corrosion, and rust resistance. The steel blade allows you to make smoothly cut and easily through a variety of meat types. However, the only drawback here is that this knife requires a little maintenance as it is not dishwasher friendly
Yoshihiro Hongasumi Blue Steel #2 is a heavy Deba knives. This knife is perfect for remove meat from cartilage and the bones of the fish. However, due to its size, I do not recommend it for cutting the big bones. The blade is designed to filet whole fish.
This knife is handcrafted in Japan and made by the traditional Japanese style. The handles is lightweight for easy hold and make the knife handy. The blade is made of Blue Steel #2 with a hardness on the Rockwell scale of 63 to 64. Yoshihiro focus on even smallest details with refined forging and polishing that will satisfied you.
This knife Deba is built with the font side is completely flat grind, a concave grind, and the back is a flat rim, all the construction allows you to cut through the food without much damage to the surface where make the cut. There is just a note that since it is made from carbon steel, which can oxidize. So, you will need to pay attention on maintenance the knife, keep the knife always dry or you can apply the oi on it to get better results.
Kai Wasabi Black Deba Knife knives guarantee the durability and sharpness for long times use without need to be replacement or falling apart. The Kai 6715D is designed with razor-sharp edge for the excellent performance. I live its designed with a Japanese single bevel and European shape double-bevel.
What I like most about Kai knife is its high quality construction that made of Daido (1K6) high-carbon steel. This type stainless steel is known as its ability of retain sharp edge, sharpened easily, and corrosion resistant. This blade won’t not easy to be discolored or stained even if you use it for some type of food that contain acidic ingredient. The blade is coated with attractive bead-blasted finish.
The handle is designed with D-shaped handle with ergonomic technology for easy and convenient holding and a firmly grip. Pakkawood material of the handle is premium high quality material that makes it is impervious to heat and do not be affected by moisture. The handle ensures you have the nice grip and well balance for smoothly and consistent slices. The only drawback here is that this knife is not strong enough to cut through bone.