Estaz Chenille-Medium (15mm ) & Petite ( 8mm ) is a twisted mylar chenille. It has pearlized fibers. The Medium is often used for eggs and comets. This is a standard material for the Salmon River. It is used for stonefly bellies and also for big comets.
Here’s a tip you won’t get from “the Other Guys”. Estaz eggs couldn’t be easier, use a large short shank egg hook. Start Flo orange thread, run the thread down the shank, skin the end off of medium size Estaz, advance thread. Make 3-4 tight wraps, pull tight, tie off and whip the end. This is a great fly. I use Opal Blue, Purple. Shrimp Pink, Chartreuse and Orange. Killer fly… THE Estaz Egg.