Which is cheaper, the Serica Ref. 5303 Diving Chronometer or the MKII Project 300?

At MSRP the Serica Ref. 5303 Diving Chronometer is the cheaper of the two at $1,768, against $1,995 for the MKII Project 300 — a $227 gap before any retailer discounting.

Which is bigger, the Serica Ref. 5303 Diving Chronometer or the MKII Project 300?

The MKII Project 300 wears larger at 41.25mm versus 39mm for the Serica Ref. 5303 Diving Chronometer — a 2.3mm difference across the dial.

What movement does the Serica Ref. 5303 Diving Chronometer run compared to the MKII Project 300?

Both watches run automatic movements — the Serica Ref. 5303 Diving Chronometer uses the M100 COSC and the MKII Project 300 uses the ETA 2824-2.

Side by side

Serica Ref. 5303 Diving ChronometervsMKII Project 300

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

Add a watch

Serica Ref. 5303 Diving Chronometer

5303-1-diving-chronometer

MSRP $1,768

MKII Project 300

project-300-big-t-date-100

MSRP $1,995

At a glance

11 of 29 specs differ

Diameter

Ref. 5303 Diving Chronometer39mm

Project 30041.25mm

Power Reserve

Ref. 5303 Diving Chronometer42h

Project 300—

Water Resistance

Ref. 5303 Diving Chronometer300m

Project 300300m

MSRP

Ref. 5303 Diving Chronometer$1,768

Project 300$1,995

Full specifications

Case

4 specs

Crystal & Dial

3 specs

AR Coating

Yes

Inner

Dial Color

Enamel Black

—

Lume

Super-LumiNova

None

Movement

3 specs

Caliber

M100 COSC

ETA 2824-2

Power Reserve

42h

—

Complications

COSC

None

Pricing

1 specs

MSRP

$1,768

$1,995

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Serica Ref. 5303 Diving ChronometervsMKII Project 300

At a glance

Full specifications

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