Gammarus shells are pre-cut, pre-marked, and pre-colored for creating ultra-realistic scuds with the greatest of ease. Just tie these shells in by their built-in tabs (or trim them for smaller hook sizes) and tie your scud as usual. The soft, malleable material melds to the top of your scud and is semi-translucent to let just the right amount of the under dubbing color to show through. You'll love the results! Sizes: (XX-Small (for hook sizes: 14-16, 21-pcs/pack), X-Small (sizes: 12-14, 18-pcs/pack), Small (sizes: 10-12, 18-pcs/pack), Medium (sizes: 8-10, 15-pcs/pack).