EP Fibers An innovative material that has enjoyed explosive popularity, EP Fibers are an amazingly translucent and durable material that is able to withstand considerable abuse from repeated strikes. The fibers are softer than Bucktail but stiffer than Marabou and they undulate and move in the water to imitate the natural movement of baitfish. The material also sheds water quickly on the pickup, so it is lighter to cast and reduces the need for false casting. When your fly gets mangled by a nasty Striper or other fish, "comb out" the materials on your fly and it will work like new!