Way back in time, fly tackle manufacturers decided they needed to standardize things to make it easier for anglers when deciding what tackle to buy. The earlier fly line designations were done with letters, instead of the number system we use now. For many of you collecting older fiberglass & bamboo fly rods, these letters are the only designation on your rod. However, at one point when they were phasing in our current number system some rods had both letters & numbers. So, if you weren't fly fishing back in the ol' letter days, you're going to need some kind of de-coder ring to make sense of the old letters. Well, here's what the old line letters translate to in our modern system:
HFH = DT4 / HFG = WF4
HEH = DT5 / HEG = WF5
HDH = DT6 / HDG = WF6
HCH =DT7 / HCF = WF7
GBG = DT8 / GBF = WF8
GAG = DT9 / GAF = WF9
GAAG = DT10 / GAAF = WF10
GAAAG = DT11 / GAAAF = WF11
GAAAAG = DT12 / GAAAAF = WF12