Side by side

Jack Mason Strat-o-timer GMTvsSeiko Prospex Sea 1968 Heritage Diver's GMT

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

Strat-o-timer GMT
Jack MasonStrat-o-timer GMT
MSRP $1,099
Prospex Sea 1968 Heritage Diver's GMT
SeikoProspex Sea 1968 Heritage Diver's GMT
MSRP $1,500
What people say

Owners + reviewers, side by side

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

Jack Mason Strat-o-timer GMT

Owners widely praise the Jack Mason Strat-o-timer GMT for its impressive fit and finish, excellent value, and true traveler GMT complication, especially considering its price point. Reviewers and owners alike highlight the comfortable 40mm tonneau case, sapphire crystal bezel, and retro styling. Some owners note the hour markers are "chubby" but do not affect legibility, and the strap ends are slightly large. One owner describes the 7-link bracelet as rivaling luxury brands. On balance, owners and reviewers rate the Jack Mason Strat-o-timer GMT highly for its build quality and value proposition.

Seiko Prospex Sea 1968 Heritage Diver's GMT

The Seiko Prospex Sea 1968 Heritage Diver's GMT is widely praised for its build quality, finishing, and comfortable wearability, offering good value for its price point. Owners and reviewers highlight the attractive silver/white sunray dial, blue ceramic bezel, and the premium feel of the improved bracelet clasp with excellent micro-adjustment. The Caliber 6R54 movement provides a 72-hour power reserve, and real-world accuracy often exceeds its stated range of +25 to -15 seconds per day, with some owners reporting figures around +3 to +5 seconds per day. However, the caller-style GMT functionality is a point of contention for some, who find the GMT scale difficult to read and prefer a flyer GMT at this price. Some also find the crown position at 4 o'clock undesirable, and a few note a lack of dial contrast or illegibility of the inner bezel.

At a glance

11 of 29 specs differ
Diameter
Strat-o-timer GMT40mm
Prospex Sea 1968 Heritage Diver's GMT42mm
Power Reserve
Strat-o-timer GMT42h
Prospex Sea 1968 Heritage Diver's GMT72h
Water Resistance
Strat-o-timer GMT200m
Prospex Sea 1968 Heritage Diver's GMT200m
MSRP
Strat-o-timer GMT$1,099
Prospex Sea 1968 Heritage Diver's GMT$1,500

Full specifications

Case

4 specs
Category
Diver
Diameter
40mm
42mm
Thickness
13.2mm
12.9mm
Lug-to-Lug
47mm
48.6mm

Crystal & Dial

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

Movement

3 specs
Caliber
Miyota 9075
6R54
Power Reserve
42h
72h
Jewels
25
24

Pricing

1 specs
MSRP
$1,099
$1,500
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