Side by side

Smiths BABY SPEEDBIRD PRS-51vsSmiths NATO PRS-40 AUTOMATIC

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

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BABY SPEEDBIRD PRS-51
SmithsBABY SPEEDBIRD PRS-51
NATO PRS-40 AUTOMATIC
SmithsNATO PRS-40 AUTOMATIC
MSRP $315
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Buy used on eBay ↗
Buy from Smiths ↗
Buy used on eBay ↗

At a glance

8 of 29 specs differ
Diameter
BABY SPEEDBIRD PRS-5136mm
NATO PRS-40 AUTOMATIC40.2mm
Power Reserve
BABY SPEEDBIRD PRS-51—
NATO PRS-40 AUTOMATIC50h
Water Resistance
BABY SPEEDBIRD PRS-51100m
NATO PRS-40 AUTOMATIC100m
MSRP
BABY SPEEDBIRD PRS-51—
NATO PRS-40 AUTOMATIC$315

Full specifications

Case

4 specs
Diameter
36mm
40.2mm
Thickness
11.4mm
12.25mm
Lug-to-Lug
42mm
54.7mm
Lug Width
18mm
22mm

Crystal & Dial

1 specs
Lume
SuperLuminova
None

Movement

2 specs
Caliber
Miyota 9015
Seiko 6R15
Power Reserve
—
50h

Pricing

1 specs
MSRP
—
—
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