Side by side

Fortis Flieger F-43 BicompaxvsSeiko King Seiko KSK

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
King Seiko KSK
SeikoKing Seiko KSK
MSRP $1,900

At a glance

14 of 29 specs differ
Diameter
Flieger F-43 Bicompax43mm
King Seiko KSK36.1mm
Power Reserve
Flieger F-43 Bicompax58h
King Seiko KSK72h
Water Resistance
Flieger F-43 Bicompax200m
King Seiko KSK100m
MSRP
Flieger F-43 Bicompax$4,180
King Seiko KSK$1,900

Full specifications

Case

6 specs
Category
Chronograph
Dress
Diameter
43mm
36.1mm
Thickness
14.5mm
11.6mm
Lug-to-Lug
43mm
Lug Width
22mm
19mm
Water Resistance
200m
100m

Crystal & Dial

4 specs
Crystal Shape
Flat
Box
AR Coating
Inner
Anti-reflective coating on inner surface
Dial Color
Original
Black
Lume
None
LumiBrite on hands and index(es)

Movement

3 specs
Caliber
Sellita SW510 BH a
6R51
Power Reserve
58h
72h
Jewels
27
24

Pricing

1 specs
MSRP
$4,180
$1,900

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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 King Seiko KSK

The King Seiko KSK is widely praised for its refined finishing, with owners and reviewers noting its sharp case, faceted lugs, and well-executed dial indices, often comparing its polishing favorably to Grand Seiko. Enthusiasts appreciate its slim, retro design, with some stating it wears smaller than its official size due to the cushion case and close-to-the-wrist feel. The use of the slimline Calibre 6L35 movement is seen as an upgrade, maintaining the watch's slender profile, though some owners express concern over the price point and the perceived value of the movement. Accuracy figures vary, with one owner reporting +5 to +7 seconds per day, while another notes +15/-10 seconds per day. Some owners have noted minor quality control issues such as misaligned screws or a burr on a hand. On balance, owners and reviewers rate the King Seiko KSK highly for its exceptional case and dial finishing at its price point.

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