The Tentagraph, an automatic high-beat chronograph, is the first watch of its kind from Grand Seiko. Powered by the new Caliber 9SC5, which uses the Caliber 9SA5 as its base, it is emblematic of the next generation of Grand Seiko sports watches, both for its technological innovation and its equally stunning Evolution 9 Style. With a power reserve of 72 hours, the Tentagraph is the longest-running 10-beat chronograph on the market today. And its design has been fully updated for active use and easy reading while in motion.