Hamilton Jazzmaster Open Heart AutovsSpinnaker Dumas GMT
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At a glance
11 of 29 specs differFull specifications
Case
7 specsCrystal & Dial
1 specsMovement
2 specsPricing
1 specsFollow this matchup
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Owners + reviewers, side by side
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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 praise the Spinnaker Dumas GMT's satisfying lume, including on the crown, and good finishing, with one owner finding it wears well on a 17cm wrist. The watch features a Seiko NH34A GMT movement and a blue gradient dial. Reviewers note its 44mm diameter and 209g weight on the bracelet make it unsuitable for smaller wrists.
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