I have used these Semperfli threads for over a year now and can thoroughly recommend them for all types of fly tying. The Nano silk was a revelation to me! It is so unbelievably strong that putting sufficient tension on thread is never going to be a problem (but you might manage to accidently cut through some materials with it). Use of a ceramic bobbin is recommended especially for the Nano silk.
Classic waxed thread
Some of the available colours of Classic waxed thread
Semperfli’s classic waxed thread was developed for use by fly tyers, it is an extruded our polyester thread which lies flatter than other threads giving more grip and has a light wax coating to enhance its grip. The 8/0 thread is 40% stronger than comparable threads. The flat profile makes the thread easy to split. 240 yards of thread are contained on each spool and the thread is available in three dimensions, 12/0 for small flies, 8/0 for the normal range of sizes and 6/0 for large flies.
Some of the available colours of Nano silk
Semperfli’s Nano silk is a multi-strand GSP product and is very strong for its size, an obvious advantage. Nano silk is pretty much unbreakable when used for fly tying. It lays flat and can be readily divided using a dubbing needle for spinning with other materials. Splitting thread to form a rudimentary dubbing loop lends itself to endless possibilities in terms of creating hackles or dubbed bodies with fur and feather. This silk is available in several sizes from the immensely strong 200D (3/0) for large salt water patterns, 100D (6/0) for pike flies and the like, 50D (12/0) for salmon flies, 30D (18/0) trout flies and for those tiny hooks sizes 18 to 32, Pro size 20D (24/0). So there is a Nano silk to suit all your purposes!