Tissot PRX Powermatic 80 40mm T137.407.11.051.01 Automatic Men’s WatchThe Tissot PRX Powermatic 80 (Model T137. 407. 11. 051. 01) features a striking black chameleon gradient dial that changes with the light, evoking the beauty of dusk and dawn. Its 40 mm tonneau shaped stainless steel case houses the self winding Powermatic 80 movement with a patented Nivachron hairspring for precision and reliability. With up to 80 hours of power reserve and a see through caseback, this watch is both functional and visually