Side by side

Spinnaker Cahill AutomaticvsSeiko Prospex Sea

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

Cahill Automatic
SpinnakerCahill Automatic
MSRP $350
Prospex Sea
SeikoProspex Sea
MSRP $625

At a glance

11 of 29 specs differ
Diameter
Cahill Automatic42mm
Prospex Sea43.8mm
Power Reserve
Cahill Automatic40h
Prospex Sea41h
Water Resistance
Cahill Automatic200m
Prospex Sea200m
MSRP
Cahill Automatic$350
Prospex Sea$625

Full specifications

Case

4 specs
Diameter
42mm
43.8mm
Thickness
13.7mm
12.8mm
Lug-to-Lug
51mm
48.7mm
Material
316L Stainless Steel
Stainless Steel

Crystal & Dial

3 specs
AR Coating
Inner
Anti-reflective coating on inner surface
Dial Color
Green
Black
Lume
None
LumiBrite on hands, index(es) and bezel

Movement

3 specs
Caliber
SII NH35A
4R35
Power Reserve
40h
41h
Jewels
25
23

Pricing

1 specs
MSRP
$350
$625

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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.

Spinnaker Cahill Automatic

Owners widely praise the Spinnaker Cahill Automatic for its attractive vintage-inspired design, comfortable wearability on smaller wrists, and good timekeeping, with one owner specifically noting the large "maxi" indices and NATO strap as highlights. However, some find the lume application uneven and note the use of a mineral crystal. A significant concern raised by one owner is a report of internal component failures and a perceived lack of quality control within the brand. On balance, the Spinnaker Cahill Automatic is well-regarded by owners for its style and value, particularly at specific price points, despite some noted manufacturing inconsistencies.

Seiko Prospex Sea

The Seiko Prospex Sea is widely praised for its excellent value, solid build quality, and comfortable wearability, with many models featuring impressive lume and attractive dials. Owners and reviewers highlight the modern upgrades on classic designs, such as drilled lugs and reliable movements with hacking and hand-winding capabilities. Some models are noted for their refined case finishing and scratch resistance. Accuracy figures vary, with one owner reporting approximately 4 seconds fast per day, while others find the movements offer good performance for the price. Concerns raised by owners and reviewers include clasps that can feel generic or cheap, and lug widths that some find disproportionate to the case size on certain models. The thickness and weight of some Prospex Sea watches are also noted as substantial. The GMT function on specific models is considered secondary and difficult to read for true travel purposes.

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