My favorite is 210 Flat Waxed Danville. Some colors I have to use the Danville when not in Flat waxed is Flymaster Plus and it's good too. Next would be 140 and other than Danville for some colors I also like Ultra Thread in 140. I only use 140 if I can't get the color in 210 or if I am tying small jigs like maybe 1/64 or something like that. Other thins I may use it for other reasons and on flies 140 is used, but usually even smaller thread for that. Some go down to 14/0 and even less.

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