We have been selling Orvis Super Strong tippet and leaders here at the shop for way over 20 years now. They has always been a benchmark in \"trout\" type leaders. Now Orvis claims they have improved it......Although we think this mostly marketing bs, the bottom line is that these are very good and staple for standard and trout type fly fishing. Here is what they had to say on their website: Meet the ideal all-around freshwater material. The wet knot strength of SuperStrong� is higher than any other nylon material, meaning when that big brown chomps on your hopper, you can finish the fight without fear of breakage. With a perfectly balanced blend of elasticity, knot strength, and suppleness, SuperStrong is versatile and adaptable. Nylon. Imported. Orvis SuperStrong Plus Leaders come two to a pack and these are the most popular 9\' variety. 0X= 14.9 lb 1X= 12.7lb 2X= 9.8lb 3X= 8.5lb 4X= 6lb 5X= 4.4lb 6X= 3.3lb 7X= 2.3lb