Which is cheaper, the Boldr Blastoise or the Sinn U18?

At MSRP the Boldr Blastoise is the cheaper of the two at $449, against $3,488 for the Sinn U18 — a $3,039 gap before any retailer discounting.

Which is bigger, the Boldr Blastoise or the Sinn U18?

The Sinn U18 wears larger at 44mm versus 40mm for the Boldr Blastoise — a 4mm difference across the dial.

Which has better water resistance, the Boldr Blastoise or the Sinn U18?

The Sinn U18 is rated to 2000m versus 200m for the Boldr Blastoise.

What movement does the Boldr Blastoise run compared to the Sinn U18?

Both watches run automatic movements — the Boldr Blastoise uses the Seiko (SII) NH37 and the Sinn U18 uses the Sellita SW300-1.

Side by side

Boldr BlastoisevsSinn U18

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

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Boldr Blastoise

MSRP $449

See the full Blastoise

Sinn U18

U18

MSRP $3,488

At a glance

18 of 29 specs differ

Diameter

Blastoise40mm

U1844mm

Power Reserve

Blastoise—

U1842h

Water Resistance

Blastoise200m

U182,000m

MSRP

Blastoise$449

U18$3,488

Full specifications

Case

8 specs

Diameter

40mm

44mm

Thickness

0mm

15.5mm

Lug-to-Lug

49.5mm

—

Lug Width

20mm

22mm

Material

Stainless Steel

high-strength

Finish

—

Water Resistance

200m

2000m

Caseback

—

Crystal & Dial

5 specs

Crystal Shape

—

AR Coating

—

Dial Color

Blastoise

Black

Indices

—

Lume

Super-LumiNova

None

Movement

4 specs

Caliber

Seiko (SII) NH37

Sellita SW300-1

Beat Rate

0 vph

28,800 vph

Power Reserve

42h

Jewels

Pricing

1 specs

MSRP

$449

$3,488

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Boldr BlastoisevsSinn U18

At a glance

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