Hareline Flat End Eye Glass Rattles can be tied into your favorite streamer patterns to produce a slight rattle on the strip retrieve. The glass rattles are flat on the ends so that eyes can be glued on. The rattle itself is hardly noticeable on the finished fly when the eyes have been glued on. Although the rattle is very subtle, these rattle eyes certainly stir up some fly tying ideas on crayfish and shrimp patterns and in colored water situations.