The Griffin Hair Stacker is a must have tool for tying wings on streamers, wet flies and dry fly patterns that call for hair fibers to be aligned. The hair stacker is a tool used to level the tips of hair. Simply place a small bundle of hair into the Griffin Hair Stacker and tap it on a table a few times, this will allow the tips to fall in line. Then pull the tube out and remove the now perfectly aligned hair fibers.