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Seiko › Field › Prospex › SPB155

Seiko SPB155

Also covers SPB159: the same watch in other colors or straps.

Prospex · Land. Sold new

Video reviews

The Seiko Baby Alpinist SPB155 is a Value Packed Explorer Alternative
Teddy Baldassarre Reviews · YouTube
The Best Everyday Field Watch? - Seiko Baby Alpinist SPB155 Review
HICONSUMPTION · YouTube

Videos are made by independent reviewers and play from YouTube; they’re not ours. We picked ones that name this reference. Own one? Share your photos.

Where to buy

New · authorized

Seiko’s own warranty.

New · grey market (unauthorized)

Often cheaper. Covered by the store’s own warranty, not Seiko’s.

Pre-owned

Check condition, box and papers. Usually no warranty.

Search links show live listings, so check the exact reference before you buy. Prices change; each one shows when we checked it. We may earn a commission from some links. It doesn’t change your price or which stores we list. Authorized vs grey market vs pre-owned.

Colors and versions (2)

Same case, movement and size; the versions differ in dial color, bezel or strap. Each reference number below is a separate model you can search for.

ReferenceComes onPriceStatusLook at it / buy
SPB155—$725Sold newSee it at Seiko · eBay · Jomashop
SPB159Leather strap—DiscontinuedeBay · Jomashop

The basics

Price
$725
Seiko US list, 2026-10-23
Size
38 mm × 12.9 mm
46 mm lug to lug
Strap width
20 mm
Any 20 mm strap fits
Water resistance
200 m
Sapphire crystal
Yes
Lume
Hands and markers
Screw-down crown
Yes
Will it fit my wrist?

Rough rule of thumb from lug-to-lug length (46 mm), not a promise. Wrist shape matters; try one on if you can.

How it works day to day

Movement
Automatic, hand-winding
Caliber 6R35, rated +25 to -15 seconds per day
Bezel
No rotating bezel listed
Hacking seconds
Yes
Seconds hand stops when you pull the crown, so you can set the time exactly
Hand-winding
Yes
Power reserve
About 70 hours

Similar watches

Compare

SPB121 vs SPB155: Two Prospex field watches on the same 6R35 movement.

Sources