Side by side

Hamilton American Classic Day Date AutovsSeiko King Seiko KSK

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

What people say

Owners + reviewers, side by side

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

Hamilton American Classic Day Date Auto

Owners widely praise the Hamilton American Classic Day Date Auto for its legible dial, well-integrated day-date complication, and vintage military aesthetic. The 40mm to 42mm case is noted to wear smaller than its dimensions suggest, and the complication is considered well-executed for its price point. However, the lume is criticized for poor intensity and longevity, and the mirror-polished bezel is flagged as a scratch magnet. The stock leather strap is also described as stiff. Overall, owners rate the Hamilton American Classic Day Date Auto highly for its attractive vintage styling and functional day-date complication at an accessible price.

Seiko King Seiko KSK

Owners and reviewers widely praise the King Seiko KSK's sharp, faceted case design and harmonious mid-century aesthetic. Its compact 38.1mm or 37mm size and slim 10.7mm thickness are noted as highly wearable. However, accuracy is a point of contention, with one reviewer reporting a wide range of +25 to -15 seconds per day for the 6R31 movement, while others criticize the standard 6R movement as too thick and a departure from the brand's history. Water resistance is consistently cited as limited to 50 meters, and one owner reported misaligned screws on the caseback and clasp. On balance, owners and reviewers find the King Seiko KSK appealing for its design and wearability, though the movement choice and accuracy are significant drawbacks for some.

At a glance

13 of 29 specs differ
Diameter
American Classic Day Date Auto42mm
King Seiko KSK38.3mm
Power Reserve
American Classic Day Date Auto80h
King Seiko KSK72h
Water Resistance
American Classic Day Date Auto50m
King Seiko KSK100m
MSRP
American Classic Day Date Auto$1,245
King Seiko KSK$2,000

Full specifications

Case

5 specs
Diameter
42mm
38.3mm
Thickness
11.55mm
11.7mm
Lug-to-Lug
0mm
46mm
Lug Width
22mm
19mm
Water Resistance
50m
100m

Crystal & Dial

4 specs
Crystal Shape
Box
AR Coating
Anti-reflective coating on inner surface
Dial Color
Grey
Lume
None
LumiBrite on Hands

Movement

3 specs
Caliber
H-30
6R55
Power Reserve
80h
72h
Jewels
0
24

Pricing

1 specs
MSRP
$1,245
$2,000
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