The SBGM221 is widely considered a fantastic choice and a strong representation of Grand Seiko's dedication to craftsmanship and precision. Its elegant design, reliable movement, and comfortable wearability make it a compelling choice for those seeking a high-end true GMT watch with a classic aesthetic. The true GMT function allows the local hour hand to be set independently, making it convenient for travelers to adjust for different time zones without stopping the watch or affecting the minutes. Powering this GS is the cal. 9S66 which is regulated to an impressive standard of +5 to -3 seconds per day, exceeding the requirements of COSC specification. The 9S66 utilizes MEMS technology for lightweight and precise escape wheel and pallet fork, and Grand Seiko's proprietary Spron 610 alloy for the hairspring, ensuring resistance to magnetism, shock, and temperature changes.
