Watch Omega - Omega Women's 3802.73.51 Speedmaster Reduced Automatic Shiny Black Leather Watch

The mother-of-pearl dial is supplemented by an Arabic numeral display, thin silver baton hands with luminosity (and seconds hand), and small seconds indexes. The watch case measures 41mm (1.61 inches) and 12mm thick (0.47 inches). Other features include water resistance to 100 meters (330 feet)--offering protection from accidental splashes as well suitable for swimming, snorkeling, and light recreational diving--and a hesalite acrylic crystal, which is resistant to temperature changes, high pressure, and shocks.

Automatic Watch Movement
An automatic watch is self-winding, and its movement has a reserve that must be at least partially filled prior to being worn. This is done by shaking and winding the timepiece manually. In order for an automatic timepiece to keep a reserve, it must be worn daily for 8 hours of active wear. This watch as a 40-hour power reserve.

How to Use a Tachymeter
A tachymeter is an instrument for measuring speed. It is a chronograph with a graduated dial on which speed can be read off in kilometers per hour based on 1000 meters distance. For example, the chronograph indicates that the distance of one kilometer has been covered in 30 seconds. The corresponding point on the tachymeter scale indicates 120, and thus the speed is 120km per hour.