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 Watch72h
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$3,600

Full specifications

Case

3 specs
Diameter
39mm
42.6mm
Thickness
12.2mm
14.1mm
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
8L45
Power Reserve
42h
72h
Jewels
25
35
Complications
COSC
None

Pricing

1 specs
MSRP
$1,768
$3,600

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 1968 Heritage Diver's Watch is widely praised for its excellent quality and finishing, with reviewers and owners noting its GS-level craftsmanship and Zaratsu-inspired polishing. Owners appreciate its refined design, comfortable case shape, and the 4:00 crown position, with some finding it more manageable on the wrist than other models. The Caliber 8L45 movement offers a 72-hour power reserve and accuracy within -5/+10 seconds per day, and the bracelet features an improved clasp with an extension system. However, some find the price point high, and one reviewer noted the unsigned winding crown as a missed opportunity. On balance, owners and reviewers rate the Seiko Prospex Marinemaster 1968 Heritage Diver's Watch highly for its premium finishing and tool-like appearance at its price point.

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.