U-boat watch. Darkmoon 44mm Black IP Bronze. Stainless steel case with IP bronze treatment. Domed sapphire crystal filled with special oil that emphasizes the dial, creating an optical effect of a more intense black and higher legibility. Innovative locking system with quick battery replacement. Black dial. Laser cut strap handmade from hand-finished calf leather. Steel buckle with IP bronze treatment. Swiss quartz movement.