I find the flourocarbon line to be graet leader material, ie: berkley vanish. but you have to go up in line test, if you use 10lb mono main go with the 12lb flouro. i use 12lb mono main and 14lb flouro. leader always breaks before the main line. the real secret in tying the dang stuff onto you swivel, it makes great bait loops but other knots are just a pain. here is the secret, use a modified cinch knot to your swivel, thats two times through then pull the loop tight wrap no more than five times around your main line, put the tag end only through the one loop, there should be only one if you pulled it tight before wrapping. put the whole works in your mouth and really swish some spit on the thing pull it tight really slowly keeping it wet in your mouth the whole time. if you hear or feel any crackling sounds while your tightening the knot start over cuz it'll break. give the knot a couple good tuggs when done just to make sure. this all sounds like a pain in the a$$ but i am convinced the stuff really works. i have caught quite a few big steelies with the stuff and haven'y broken one off since i figured out how to tie the stuff. good luck