Fortis Flieger F-39vsMarathon Steel Navigator SSNAV Auto
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At a glance
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Case
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Owners + reviewers, side by side
Synthesized for each watch independently from owner discussions, enthusiast forums, written reviews, and video reviewers.
Owners and reviewers widely praise the Fortis Flieger F-39 for its robust build quality, excellent finishing often compared favorably to more expensive watches, and legible utilitarian dial with distinctive color accents. The watch is noted for its precise bidirectional bezel action, excellent lume, and comfortable wearability, with one owner reporting accuracy of 1 second fast per day. Some reviewers flag the 39mm case as wearing large due to its lug-to-lug distance, and the 38-hour power reserve of the Sellita SW 200-1 based UW-30 movement is cited as a limitation, though newer versions feature a 70-hour power reserve. Overall, owners and reviewers highly regard the Fortis Flieger F-39 for its tool watch aesthetic and impressive machining and build quality at its price point.
The 200m water resistance is a notable strength. Reviewers did not reach a consensus on any weaknesses.
The Marathon Steel Navigator SSNAV Auto is praised for its high-accuracy quartz movement, with owners noting its comfort and reliable performance. Reviewers highlight its functional tool-watch appeal, featuring a sandblasted steel case, tritium tubes for constant low-light visibility, and 100-meter water resistance. One owner finds the 41mm case runs a bit small. The Marathon Steel Navigator SSNAV Auto utilizes an ETA F06.412 quartz movement with a claimed accuracy of +/- 10 seconds per year and includes a GMT bidirectional bezel. Overall, owners and reviewers rate the Marathon Steel Navigator SSNAV Auto highly for its comfortable wear and dependable, high-accuracy quartz movement.
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