Hello to all,
I have the Fisher catalog from 89-90. In it are listed the following fly rod series:
4 piece rods:
Original series
Zephyr series
GT-40 series
Sterling series
Presidential series
Plus there are listed multipiece rods which convert to different rod lengths.

The Sterling series feature " a superior high strain modulus graphite HS4".
The GT-40 series list "HS4 is a superior, higher modulus, high strain graphite that has replaced IM6 in Fisher's inventory of materials."
The Original Series state "......well-priced, full F80 graphite......"

Dick xfishcop