Limited Edition of 1981 Pieces.
Hamilton Watch Khaki X-Wind Auto Chrono Limited Edition H77796135. Inside the case is the H-21-Si, the first Hamilton chronograph movement with a silicon hairspring. This material makes the movement more precise as silicon is non magnetic and less sensitive to shocks. The former is an important feature for pilots because they often stay in environments with high magnetic fields, such as airports. In addition, the movement has been precision certified by COSC as a chronometer.