Side by side

Fortis Flieger F-43 BicompaxvsSeiko 5KX

The numbers, the dial colors, the calibers — laid out so you can stop flipping between tabs.

Flieger F-43 Bicompax
FortisFlieger F-43 Bicompax
MSRP $4,180
5KX
Seiko5KX
MSRP $350

At a glance

12 of 29 specs differ
Diameter
Flieger F-43 Bicompax43mm
5KX42.5mm
Power Reserve
Flieger F-43 Bicompax58h
5KX41h
Water Resistance
Flieger F-43 Bicompax200m
5KX100m
MSRP
Flieger F-43 Bicompax$4,180
5KX$350

Full specifications

Case

5 specs
Category
Chronograph
Diver
Diameter
43mm
42.5mm
Thickness
14.5mm
13.4mm
Lug-to-Lug
46mm
Water Resistance
200m
100m

Crystal & Dial

3 specs
Crystal
Sapphire
Hardlex
Dial Color
Original
Black
Lume
None
LumiBrite on hands and index(es)

Movement

3 specs
Caliber
Sellita SW510 BH a
4R36
Power Reserve
58h
41h
Jewels
27
24

Pricing

1 specs
MSRP
$4,180
$350

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What people say

Owners + reviewers, side by side

Synthesized for each watch independently from owner discussions, enthusiast forums, written reviews, and video reviewers.

Fortis Flieger F-43 Bicompax

Owners widely praise the Fortis Original for its tool-watch aesthetic, legibility, and robust construction, with many noting excellent lume that lasts all night and precise day/date changes at midnight. The brushed stainless steel case is well-finished, and the 38mm size is considered comfortable and well-weighted despite being smaller than modern watches. Accuracy figures range from +2 seconds/day to +8 seconds/day, and some owners compare Fortis quality favorably to Omega. However, some users find the MSRP too high compared to brands like Sinn and Damasko, and one owner reported internal parts dislodging from a limited edition model. Concerns have also been raised about stripped lug screws on B-42 models and potential parts shortages due to past bankruptcy protection filings. Overall, owners rate the Fortis Original highly for its durable construction and tool-watch functionality at a competitive price point.

Seiko 5KX

Owners widely praise the Seiko 5 Sports SKX series for its strong lume and comfortable wearability, with many noting its compact feel due to a short lug-to-lug length. The NH36 movement's accuracy varies, with typical performance between +/-5 to 10 seconds per day, though some report better. A lack of screw-down crown and ISO certification are noted drawbacks for its water resistance. Some owners find the bracelet to be of cheaper construction with hollow links, and a few have reported quality control issues. The consensus is that the Seiko 5 Sports SKX series offers good value for its price, appealing to those who appreciate its tool-like nature and iconic lineage.

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