Tudor Black Bay 31 S&G, 31mm 316L steel case with polished and satin finish, black with diamond hour markers, fixed bezel in steel covered by a 0.3mm 18 ct yellow gold cap, manufacture calibre MT5201 (COSC) self-winding mechanical movement with bidirectional rotor system integrated construction, yellow gold center links at 6 and 12 o’clock, remaining center links in steel covered by a 0.2mm 18 ct yellow gold cap, “T-fit” folding clasp with safety catch, the logo on the catch is made of yellow gold, flat sapphire crystal, waterproof to 100m (330 ft)