Side by side

Serica Ref. 5303 Diving ChronometervsSeiko Monster

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
Monster
SeikoMonster
MSRP $550

At a glance

13 of 29 specs differ
Diameter
Ref. 5303 Diving Chronometer39mm
Monster42.4mm
Power Reserve
Ref. 5303 Diving Chronometer42h
Monster41h
Water Resistance
Ref. 5303 Diving Chronometer300m
Monster200m
MSRP
Ref. 5303 Diving Chronometer$1,768
Monster$550

Full specifications

Case

4 specs
Diameter
39mm
42.4mm
Thickness
12.2mm
13.4mm
Lug-to-Lug
46.5mm
49.4mm
Water Resistance
300m
200m

Crystal & Dial

4 specs
Crystal
Sapphire
Hardlex
AR Coating
Yes
Inner
Dial Color
Enamel Black
Black
Lume
Super-LumiNova
LumiBrite on hands, index(es) and bezel

Movement

4 specs
Caliber
M100 COSC
4R36
Power Reserve
42h
41h
Jewels
25
24
Complications
COSC
None

Pricing

1 specs
MSRP
$1,768
$550

Follow this matchup

Get a note when Serica Ref. 5303 Diving Chronometer vs Seiko Monster 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 Monster

Owners widely praise the Seiko Prospex Sea for its excellent value, robust build, and superb lume, with many noting its comfortable wearability. Reviewers consistently highlight its impressive finishing and classic dive watch design, often comparing it favorably to older models. Some owners find the size substantial, with one noting it as big, thick, and heavy on a 6.5-inch wrist, while others find it perfect. On balance, owners and reviewers rate the Seiko Prospex Sea highly for its exceptional value and robust, classic dive watch design.

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.