The Hareline Dubbin' Feather Prepper Jr. is designed to make it easy to fold feather fibers to make wrapping hackles easy when you need to pull the fibers in one direction like needed for wet flies, steelhead flies and other streamer patterns. The Feather Prepper Jr. is made of flexible foam and works well even with the tiniest and longest feathers. The JR. size has half the slots and is about half the size of the Feather Prepper.