The MRG-B2000GA-1A is a G-Shock 40th Anniversary release limited to 500 watches worldwide. Like the MRG-G2000GA-1A from 2019, the MRG-B2000GA-1A features a special finish created in the Gassan style of swordsmiths, which inherits 800 years of traditional sword-making techniques.
The bezel has a special Ayasugi pattern, which is also seen on Gassan sword blades from the layers of forged steel. The bezel is made of a combination of pure titanium and Ti64 titanium. A recrystallizing process and a blue-gray arc ion plating (AIP) treatment results in a unique pattern in which every bezel is one of a kind. The wear-resistant AIP treatment of the bezel and band was developed by Kobe Steel and has a hardness equal to or greater than a DLC treatment.
The case surface is also unique, with a heat-treated crystal pattern that resembles the nie pattern seen on the blade of swords. The case also has a deep hardening treatment and titanium carbide treatment, a signature feature of the MR-G series that improves strength and wear resistance.
A metal plate on the upper left side of the case is engraved with “G-SHOCK 40TH” to commemorate the anniversary. The titanium band has markings in the style of the kesho file marks seen on the handle side of the sword blade, applied by sixth-generation master swordsmith Sadanobu Gassan. The dial has a textured diamond-like pattern along with a fan motif.