When we look closely at insects and invertebrates they are not just one color but a range of mixed colors across their body. So why do we often use single color dubbing to imitate nature? That was the big question the Semperfli Pro Team was asking. As a result, they developed Dirty Bug Yarn. It is called Dirty Bug Yarn because it has multiple colors found on insects and invertebrates, whether you are tying shrimps, baetis nymphs, caddis nymphs it does not matter. Semperfli decided to blend multiple color materials into Dirty Bug Yarn Black creating a 2 ply yarn so that you can tie larger nymphs or split the 2 ply yarn for smaller flies.