The case and clasp are made of Grand Seiko’s Brilliant Hard Titanium. The alloy is brighter than traditional titanium, causing the case’s Zaratsu-polished surfaces to appear even more radiant and achieving a sparkle of quality and beauty befitting a Grand Seiko dress watch. Brilliant Hard Titanium makes the watch not only light but also highly resistant to corrosion and scratches while commanding a hardness double that of standard stainless steel.
The movement achieves a higher winding efficiency thanks to a rearrangement of the gear train and redesign of the parts, so that Caliber 9SA4 achieves a power reserve of 80 hours with 15 percent fewer crown rotations than are required to achieve the same power for Caliber 9SA5 when winding it by hand. Thanks to its svelte movement, the latest birch-inspired mechanical watch is 38.6mm in diameter and achieves a slimness of 9.95mm.
