One of the strongest and the finest in the Semperfli range of fly tying threads. The 24/0 thread will not break and can be used to create very fine heads on salmon flies and tubes, ideal for small nymphs and buzzers through to larger flies, highly versatile threads. This is ultra strong thread and flattens to almost nothing allowing you to grip into materials whilst making a tiny head for your flies.A trusted brand and a market leading fly tying thread.