Which is cheaper, the Biatec T. G. Masaryk or the Seiko Prospex Sea?

At MSRP the Seiko Prospex Sea is the cheaper of the two at $1,100, against $2,214 for the Biatec T. G. Masaryk — a $1,114 gap before any retailer discounting.

Which is bigger, the Biatec T. G. Masaryk or the Seiko Prospex Sea?

The Seiko Prospex Sea wears larger at 41.3mm versus 40mm for the Biatec T. G. Masaryk — a 1.3mm difference across the dial.

Which has better water resistance, the Biatec T. G. Masaryk or the Seiko Prospex Sea?

The Seiko Prospex Sea is rated to 300m versus 100m for the Biatec T. G. Masaryk.

Which has a longer power reserve, the Biatec T. G. Masaryk or the Seiko Prospex Sea?

The Seiko Prospex Sea carries a 72-hour power reserve against 41 hours on the Biatec T. G. Masaryk.

What movement does the Biatec T. G. Masaryk run compared to the Seiko Prospex Sea?

Both watches run automatic movements — the Biatec T. G. Masaryk uses the Sellita SW200-1 and the Seiko Prospex Sea uses the 6R55.

Side by side

Biatec T. G. MasarykvsSeiko Prospex Sea

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

Add a watch

Biatec T. G. Masaryk

MSRP $2,214

Seiko Prospex Sea

spb481j1

MSRP $1,100

At a glance

13 of 29 specs differ

Diameter

T. G. Masaryk40mm

Prospex Sea41.3mm

Power Reserve

T. G. Masaryk41h

Prospex Sea72h

Water Resistance

T. G. Masaryk100m

Prospex Sea300m

MSRP

T. G. Masaryk$2,214

Prospex Sea$1,100

Full specifications

Case

6 specs

Crystal & Dial

3 specs

AR Coating

Inner

Anti-reflective coating on inner surface

Dial Color

Beige

Black

Lume

None

LumiBrite on hands, index(es) and bezel

Movement

3 specs

Caliber

Sellita SW200-1

6R55

Power Reserve

41h

72h

Jewels

Pricing

1 specs

MSRP

—

$1,100

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Biatec T. G. MasarykvsSeiko Prospex Sea

At a glance

Full specifications

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