Bremont Supermarine 300MvsSeiko Prospex Sea 1968 Heritage Diver's GMT Watch
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At a glance
11 of 29 specs differFull specifications
Case
4 specsCrystal & Dial
3 specsMovement
3 specsPricing
1 specsFollow this matchup
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Owners + reviewers, side by side
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The Bremont Supermarine 300M is praised for its comfortable 40mm and 42mm case sizes, with owners noting the 42mm wears well on smaller wrists due to its lug design. One owner highlights the 13mm thinness of the 40mm case, considered compact for a 300m diver. The watch is priced at $1375. On balance, owners and reviewers appreciate the Bremont Supermarine 300M for its wearability and compact dimensions, especially for a dive watch.
The Seiko Prospex Sea 1968 Heritage Diver's GMT Watch offers a 300-meter depth rating and a caller-style GMT complication powered by the Caliber 6R54 movement, which provides a 72-hour power reserve. Reviewers note its refined clasp with extensive micro-adjustment. However, the movement's accuracy, ranging from +25 to -15 seconds per day, is considered a drawback by some. Overall, reviewers highlight the Seiko Prospex Sea 1968 Heritage Diver's GMT Watch as a good reminder of Seiko's value, despite the wide accuracy range of its movement.
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