Marathon Steel Navigator SSNAV-D AutovsFormex Reef 39.5 mm
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At a glance
11 of 29 specs differFull specifications
Case
6 specsCrystal & Dial
2 specsMovement
2 specsPricing
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Owners + reviewers, side by side
Synthesized for each watch independently from owner discussions, enthusiast forums, written reviews, and video reviewers.
The Marathon Steel Navigator SSNAV-D Auto is praised for its durable construction, featuring a sandblasted steel case with improved lugs, a bi-directional bezel with excellent action, and 100m water resistance. Owners appreciate the constant visibility provided by self-illuminating tritium gas tubes and the precision of its ETA F06.412 quartz movement, which offers accuracy to about 10 seconds per year. The watch includes a GMT bezel for dual timekeeping and a synthetic sapphire crystal. Overall, owners and reviewers rate the Marathon Steel Navigator SSNAV-D Auto highly for its robust tool-watch design and reliable tritium illumination.
The Formex Reef 39.5 mm is widely praised for its refined finishing, comfortable and well-proportioned case design, and impressive specifications for its price point, including COSC-certified Sellita SW300-1 movement and 300m water resistance. Owners and reviewers highlight the tool-less micro-adjust clasp and quick-release spring bars as practical features. Some reviewers note that the 22mm lug width feels slightly disproportionate to the smaller case, and the bracelet could benefit from more taper, though this is a point of contention for some owners who value the overall package. A prototype crown protrusion issue is noted as being addressed for production. On balance, owners and reviewers rate the Formex Reef 39.5 mm highly for its excellent value and well-executed design.
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