
For the Gibson and Epiphone Thunderbird bass using Gotoh style tuners, the GB7 is a direct Xtender upgrade.
In addition, the 3/8 Ultralite Xtender (with mini clover or Y key only) is a a direct upgrade.

For the Gibson and Epiphone Thunderbird bass using Gotoh style tuners, the GB7 is a direct Xtender upgrade.
In addition, the 3/8 Ultralite Xtender (with mini clover or Y key only) is a a direct upgrade.