Hamilton caliber H-21
H-21 description
The Hamilton H-21 is based on the Valjoux 7750. The H-31 is similar though based on the 7753. These movements most notable change compared to the standard version is the 60 hour power reserve.
The following elements have been modified:
- The entire kinematic chain has been refined, from the barrel to the escapement
- The escapement regulator has been suppressed, facilitating optimal reliability and precision
- The main spring has been improved to increase a typical power reserve of 60 hours.
All watches using the Hamilton H-21 movement:

H77616133
Hamilton Khaki Aviation X-Wind

H77626153
Hamilton Khaki Aviation X-Wind

H77616333
Hamilton Khaki Aviation X-Wind Black

H77646733
Hamilton Khaki Aviation X-Wind Automatic Black-Orange / Leather

H77616533
Hamilton Khaki Aviation X-Wind Black

H77696793
Hamilton Khaki Aviation X-Wind Auto Chrono Red / Carbon

H32616133
Hamilton Jazzmaster Automatic Chronograph 42mm Black Dial Bracelet

H32616533
Hamilton Jazzmaster Automatic Chronograph 42mm Black Dial

H32616153
Hamilton Jazzmaster Automatic Chronograph 42mm White Dial Bracelet

H32616553
Hamilton Jazzmaster Automatic Chronograph 42mm White Dial

H76626535
Hamilton Khaki Aviation X-Mach

H76626135
Hamilton Khaki Aviation X-Mach

H76686335
Hamilton Khaki Aviation X-Mach

H76686735
Hamilton Khaki Aviation X-Mach

H32576135
Hamilton Jazzmaster Maestro Automatic Chronograph 41mm Black Dial Bracelet

H32576515
Hamilton Jazzmaster Maestro Automatic Chronograph 41mm White Dial

H32576735
Hamilton Jazzmaster Maestro Automatic Chronograph 41mm Black Dial

H32596131
Hamilton Jazzmaster Automatic Chronograph 42mm Black Dial Bracelet

H32596731
Hamilton Jazzmaster Automatic Chronograph 42mm Black Dial

H32596151
Hamilton Jazzmaster Automatic Chronograph 42mm Silver Dial Bracelet

H32596751
Hamilton Jazzmaster Chronograph Automatic 42mm Silver Dial

H32596551
Hamilton Jazzmaster Automatic Chronograph 42mm Silver Dial / Gold Indexen

H32596141
Hamilton Jazzmaster Automatic Chronograph 42mm Blue Dial Bracelet

H32596741
Hamilton Jazzmaster Automatic Chronograph 42mm Blue Dial

H77726351
Hamilton Khaki Aviation X-Wind Automatic Silver / Rubber

H40656131
Hamilton Railroad Auto Chrono

H40656181
Hamilton Railroad Auto Chrono

H40656731
Hamilton Railroad Auto Chrono

H40656781
Hamilton Railroad Auto Chrono

H32416581
Hamilton Spirity of Liberty Chronograph Automatic Gold

H32416781
Hamilton Spirity of Liberty Chronograph Automatic

H32416981
Hamilton Spirit of Liberty Chronograph Automatic Bracelet

H32416181
Hamilton Spirity of Liberty Chronograph Automatic Gold Bracelet

H43516131
Hamilton Broadway Automatic Chronograph Steel / Grey / Bracelet

H43516731
Hamilton Broadway Automatic Chronograph Steel / Grey

H71626735
Hamilton Khaki Field Automatic Chronograph PVD / Black

H71616535
Hamilton Khaki Field Automatic Chronograph Steel / Black

H77726151
Hamilton Khaki Aviation X-Wind Automatic Silver / Bracelet

H77736733
Hamilton Khaki Aviation X-Wind Auto Chrono PVD

H71706830
Hamilton Khaki Field Auto Chrono