Side by side

Serica Ref. 5303 Diving ChronometervsSeiko Prospex Marinemaster Marinemaster 1968 Heritage Diver's Watch

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

Ref. 5303 Diving Chronometer
SericaRef. 5303 Diving Chronometer
MSRP $1,768

At a glance

12 of 29 specs differ
Diameter
Ref. 5303 Diving Chronometer39mm
Prospex Marinemaster Marinemaster 1968 Heritage Diver's Watch42.6mm
Power Reserve
Ref. 5303 Diving Chronometer42h
Prospex Marinemaster Marinemaster 1968 Heritage Diver's Watch50h
Water Resistance
Ref. 5303 Diving Chronometer300m
Prospex Marinemaster Marinemaster 1968 Heritage Diver's Watch300m
MSRP
Ref. 5303 Diving Chronometer$1,768
Prospex Marinemaster Marinemaster 1968 Heritage Diver's Watch$2,900

Full specifications

Case

3 specs
Diameter
39mm
42.6mm
Thickness
12.2mm
13.4mm
Lug-to-Lug
46.5mm
49.3mm

Crystal & Dial

4 specs
Crystal Shape
Flat
Curved
AR Coating
Yes
Anti-reflective coating on inner surface
Dial Color
Enamel Black
Black
Lume
Super-LumiNova
LumiBrite on hands, index(es) and bezel

Movement

4 specs
Caliber
M100 COSC
8L35
Power Reserve
42h
50h
Jewels
25
26
Complications
COSC
None

Pricing

1 specs
MSRP
$1,768
$2,900

Follow this matchup

Get a note when Serica Ref. 5303 Diving Chronometer vs Seiko Prospex Marinemaster Marinemaster 1968 Heritage Diver's Watch gets more votes, a community discussion, or a price drop. No account needed.

What people say

Owners + reviewers, side by side

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

Serica Ref. 5303 Diving Chronometer

Owners widely praise the Serica Ref. 5303 Diving Chronometer for its excellent wearability, definitive style, and smooth, confident bezel action. The dual scale on the bezel is noted as surprisingly useful, and the crown action, winding, and hacking are reported to work perfectly. One owner describes the Serica 5303-3 as gorgeous and unique, though another notes the crown can appear comically large. On balance, owners rate the Serica Ref. 5303 Diving Chronometer highly for its blend of unique design and robust functionality.

Seiko Prospex Marinemaster Marinemaster 1968 Heritage Diver's Watch

The Seiko Prospex Marinemaster Marinemaster 1968 Heritage Diver's Watch is praised for its premium finishing, often described as Zaratsu-like, and robust build quality, with owners finding its 42mm case and 4 o'clock crown appealing for wearability. Some reviewers note its secondary GMT function and quieter bezel clicks may not suit all preferences, while one owner reported bezel misalignment issues. The watch is powered by the Caliber 8L45 automatic movement, offering a 72-hour power reserve and an accuracy rating of -5/+10 seconds per day, though some owners question its value proposition at its price point. On balance, owners and reviewers rate the Seiko Prospex Marinemaster Marinemaster 1968 Heritage Diver's Watch highly for its exceptional finishing and refined tool-like aesthetic.

Keep exploring

More watches worth a look

Matched to the watches above on size, movement, style and price — microbrands first. Open any one to dig in.

Adjacent matchups

People also compared

Comparisons nearby in the catalog — alternatives to the watches above paired against the matchup.