A deba knife is a traditional Japanese kitchen knife primarily used for filleting fish. It features a thick, sturdy blade that is typically around 6 to 9 inches long, allowing for precise cuts and the ability to handle larger fish. The blade is single-beveled, meaning it is sharpened on one side, which helps achieve clean, smooth cuts. This knife is designed for both cutting through fish bones and skinning, making it an essential tool for sushi chefs and home cooks alike. While it excels in fish preparation, it can also be used for other proteins, showcasing its versatility in the kitchen.