Introducing the first Grand Seiko mechanical chronograph, the Tentagraph.

Just like every Grand Seiko creation, the pursuit of precision is at the heart of the new Tentagraph, whose chronograph movement features the revolutionary Hi-Beat Caliber 9SAS as its base. Like Caliber 9SAS, the new Tentagraph Caliber 9SCS beats ten times per second, ensuring high accuracy when measuring elapsed time as well as the time of day. And, thanks to its energy-efficient escapement and two barrels, the watch runs for three days even when the chronograph is in operation, making Tentagraph the 10-beat chronograph with the longest power reserve in the industry today.

Furthermore, the Tentagraph is subjected to a new and longer testing procedure. As with all Grand Seiko mechanical movements, the Tentagraph's time-of-day accuracy is assessed in six positions and at three temperatures over 17 days but, in addition, there are three more days of testing during which the accuracy is assessed in three positions while the chronograph is in operation. Thus, in total, each Tentagraph movement is tested for 20 days to ensure that it meets the Grand Seiko Standard of +S to -3 seconds per day.

With the new Tentagraph, Grand Seiko adds a new dimension to its range of sports watches and opens a new chapter in its history.The new movement features the revolutionary Dual Impulse Escapement, which efficiently transfers energy to the free-sprung balance wheel indirectly through the pallet fork and also directly from the escape wheel. MEMS technology ensures extremely precise, lightweight, and highly durable escapement parts also endows the escapement with increased energy efficiency to achieve a long power reserve.

Hallmarks of a high-quality modern chronograph, a vertical clutch and column wheel ensure high accuracy and operability. The vertical clutch eliminates any shuddering or jumping of the hands when the chronograph is engaged and enhances measurement accuracy, while the column wheel ensures precise control of the chronograph operation. The movement incorporates a three-pointed hammer, which ensures that, when the reset pusher is pressed, the hands return to zero instantly and in perfect synchronization.

The ideals of a Grand Seiko sports watch are readily apparent in this new chronograph. The powerful hands and prominent, grooved indexes of the Evolution 9 Style ensure supreme legibility. The chronograph seconds hand is gently curved down towards the dial so that the tip of the hand is as close as possible to the dial's markers and extends to the markings at the very edge of the dial. The minute hand is also gently curved to ensure the legibility of the time of day.The case and bracelet are made of high-intensity titanium, which is about 30% lighter and more scratch resistant than stainless steel to maximize durability, and the two convex pushers ensure the operability required for measuring elapsed time at the highest level.

The dial features Grand Seiko's signature "Mt. Iwate pattern," which takes inspiration from the ridged contours of the nearby mountain visible through the windows of the Grand Seiko Studio Shizukuishi, where the Tentagraph and other Grand Seiko mechanical watches are hand-assembled and adjusted. The Mt. Iwate dial first appeared in 2006, and the pattern has since become deeply associated with Grand Seiko mechanical watchmaking. The majestic peak serves as an enduring inspiration for Grand Seiko, and its choice for the brand's first mechanical chrono­ graph is both symbolic and fitting. Combined with the gentle blue hue, the dial takes the imagination upwards towards the night sky above Mt. Iwate.

Discover more about Grand Seiko and keep an eye out for new releases from the fair landing both on our websites and in our showrooms soon.