This now the industry standard in tying egg flies. It is much easier to use than egg yarn as it set on a narrow core allowing it to be wrapped around the hook easily. it is an extremely fine fibre and when wet give the feel of cotton wool almost a slushy feel. Of course when fished it creates a halo effect on its outer edges. Since its inception it has also been used in tying blobs,fabs and boobies not to mention snakes and worms.