The Tissot PRX Powermatic 80 model T1374072103100 runs on the Swiss automatic Powermatic 80.111 caliber, equipped with a Nivachron balance spring, and offers an impressive 80-hour power reserve. https://saicreationswatches.com/products/t1374072103100-tissot-unisex-t-classic-prx-powermatic-80-watch-for-men