Hamilton Jazzmaster Open Heart AutovsGruppo Gamma Peacemaker Bronze
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The Hamilton Jazzmaster Open Heart Auto is noted for its dressy yet versatile design, featuring striking gradient dials and intricately shaped cutouts that reveal the H-10 movement. It boasts an 80-hour power reserve and Nivachron hairspring. The watch is available in 36mm, 40mm, or 42mm stainless steel cases. On balance, the Hamilton Jazzmaster Open Heart Auto is appreciated for its visually engaging dial and movement display at its price point.
The smoked dial's precision cutouts offer a captivating view of the automatic movement. Legibility is compromised by the open-heart design.
Owners widely praise the Gruppo Gamma Peacemaker Bronze for its strong vintage aesthetic, featuring attractive sandwich dials and high-domed or box-shaped sapphire crystals. The bronze case is noted for developing patina and the watch is generally considered a good value. Accuracy figures vary, with one report of approximately +10 seconds per day and others stating +/-12 seconds per day. Power reserves range from 38 to 45 hours depending on the movement. One owner describes the winding action as a "dream." On balance, owners consider the Gruppo Gamma Peacemaker Bronze a well-built watch offering significant vintage appeal and value.
At a glance
13 of 29 specs differFull specifications
Case
7 specsCrystal & Dial
3 specsMovement
2 specsPricing
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