Grand Seiko is expanding its Heritage Collection with two new compact quartz watches designed for collectors who want the brand’s signature dial artistry in a smaller, slimmer case. The new references, Grand Seiko SBGX359 and SBGX361, are set to enter continuous production with worldwide availability beginning in April 2026.
What makes this release stand out is the new size standard. Both watches use a 33.0 mm stainless steel case that measures just 9.1 mm thick, making them the smallest and slimmest cases ever created for Grand Seiko’s 9F quartz series. In practical terms, that means a more comfortable fit on smaller wrists while still delivering the crisp finishing and refined proportions the Heritage line is known for.
Inside, Grand Seiko introduces the newly developed Caliber 9F51. It keeps the high-precision reputation of the 9F family with an accuracy rating of ±10 seconds per year. Although it builds on the classic 9F architecture first introduced in 1993, the 9F51 has a diameter reduced by 0.6 mm compared to the Caliber 9F61. That smaller movement footprint is a key reason Grand Seiko can achieve the notably thin 9.1 mm profile without sacrificing performance or the robust feel expected from a 9F-powered watch. The movement also includes a Twin Pulse Control Motor for high-torque hand motion, along with a backlash auto-adjust mechanism designed to keep the seconds hand aligned precisely on the markers.
The dials are the headline feature for many enthusiasts, borrowing inspiration from the Nagano region around the Shinshu Watch Studio. The Grand Seiko SBGX359 showcases a “Snowflake” dial: a textured white surface created through a controlled silver-plating and clear-coating process, finished with a tempered blue seconds hand for contrast. The Grand Seiko SBGX361 offers the “Skyflake” dial, featuring a pale blue tone paired with a wind-swept snow texture that adds depth and shifting character under different lighting.
Both models are fitted with sapphire crystals and are priced at $3,200 USD. With their compact 33 mm sizing, ultra-slim 9.1 mm cases, and the new Caliber 9F51 accuracy platform, the SBGX359 and SBGX361 aim to deliver an ideal blend of everyday comfort, high-end dial finishing, and dependable high-precision quartz performance when they launch globally in April 2026.
