Uni-Yarn is a standard, 2-strand, twisted, acrylic fly tying yarn, spooled instead of carded for convenience and to reduce wastage.

UNI-Yarn (fluorescent) is the same material as UNI-Yarn but with the extra brilliance of fluorescent treatment. While useful in many applications, it is ideal for the fluorescent butts called for on many Atlantic salmon fly patterns. The Fluo-Yarn is available in six popular colors.