TUDOR Black Bay One 31 S&G

31mm steel case, Steel and yellow gold bracelet
CASE: 31mm steel case with polished and satin finish
BEZEL: Fixed bezel in solid yellow gold
MOVEMENT: Manufacture Caliber MT5201 (COSC), tuned to -3/+5 seconds Self-winding mechanical movement with bidirectional rotor system
DIAL: Black with diamond hour markers
WINDING CROWN: Screw-down winding crown with the TUDOR rose in relief. Steel covered by a 0.1mm yellow gold cap
CRYSTAL: Flat sapphire crystal
WATERPROOFNESS: Waterproof to 100m (330 ft)
BRACELET: First center links in steel or solid yellow gold. Remaining center links are made of a steel core capped with 0.2mm of yellow gold. TUDOR "T-fit" folding clasp with safety catch. The logo on the catch is made of solid yellow gold