Gotohs take on the "Historic Deluxe" machine head that turns up so frequently, but in a rear twist. they've incorporated their exceptional "magnum thumb locking" system, making them easier to string up, and improving stability.
Differing from similar models from Schaller®, the SD90s take a push in bush, so only require an 8.5mm hole in the headstock (opposed to a 10.5mm, which is common on more modern guitars)
