70 for me would be more for fly tying, I do use some 140 tying jigs and for color I even have a couple of 6/0 Uni spools, but most is 210 for me. I do tie some flies as well, but so far have not needed to use the smaller stuff. I even have a few 14/0 and figure if I ever use that I will probably have to use a Rite bobbin to keep from breaking it, lol!

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