KAMABOKO File, is a file that is a shape of a kamaboko

Kamaboko is fish cake. This Japanese food is a processed seafood made from fish paste. This food is usually in a shape of a semicircle, which this shape in Japanese is referred to as a “Kamaboko shape”.

This may look like an ordinary half round file, but there are no tooth on the convex surface

This, actually is a flat file

Does not have tooth

In theory, the convex surface does not touch the side surface with an inverted angle from 180-90