Citizen Automatic Open Heart Black NH9131-14E Men's Watch, Design, See-Through Back, Waterproof,

[Citizen Collection: Pursuing both basic watch performance and design] A mechanical watch with a classically modern design. The open-heart design allows you to enjoy the delicate movement of the balance wheel, the heart of a mechanical watch, through a window at the 6 o'clock position on the dial. [The black dial features gorgeous pink gold hands and indexes] The dial pattern radiates from a circular window, creating a distinctive design. The case back is see-through, allowing you to enjoy the rotating weight and mechanical movement. [Mechanical automatic watch] This is a mechanical automatic watch powered by a mainspring. When you wear the watch on your wrist, the movement of your arm sets in motion a rotating weight inside the watch, automatically winding the mainspring. *You can also find instructions on how to use it in the instruction manual on the manufacturer's website (model number: 8229). [Product Details] Mechanical watch, automatic and manual winding, -20 to +40 seconds per day, approximately 42 hours (when fully wound), crystal glass, case: stainless steel, band: calfskin, water resistant to 5 ATM