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Seiko Monster
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Seiko · Prospex Sea

Seiko Monster

Diver

$550
Buy from SeikoFind used on eBay

Case

Diameter
42.4mm
Thickness
13.4mm
Lug-to-lug
49.4mm
Lug width
20mm
Material
Stainless Steel
Water resistance
200m

Crystal & dial

Crystal
Hardlex
Lume
LumiBrite on hands, index(es) and bezel

Movement

Caliber
Seiko 4R36
Type
Automatic
Power reserve
41h
Jewels
24
Hacking
No
Hand-winding
No
Complications
Time only

Seiko

Seiko's day-date automatic caliber and the in-house branded version of the NH36 with stricter quality control and finishing. The additional day wheel over the 4R35 adds the day-of-week complication without changing the movement dimensions. Found extensively in the Seiko 5 Sports and Prospex lines, it offers Seiko's proven reliability with the convenience of day-date display at a mainstream price point.

Design language

Case shape
round
Dial style
matte
Bezel
rotating
Bracelet
lug-attached
Hands
mercedes

AI-detected from the product image

Prospex Sea collection · 32 watches

62MAS
62MAS40.5mm
Captain Willard
Captain Willard42.7mm
Ice Diver
Ice Diver45mm
King Turtle
King Turtle45mm
Prospex Sea
Prospex Sea42mm
Prospex Sea
Prospex Sea41mm
Prospex Sea
Prospex Sea43.5mm
Prospex Sea
Prospex Sea41.3mm
Prospex Sea
Prospex Sea43.8mm
Prospex Sea
Prospex Sea41.7mm
Prospex Sea
Prospex Sea34mm
Prospex Sea 1965 Heritage Diver's Save the Ocean Special Edition
Prospex Sea 1965 Heritage Diver's Save the Ocean Special Edition40.5mm
19 more in this collection
Prospex Sea 1965 Heritage Diver's WatchProspex Sea 1965 Heritage Diver's Watch PADI Special EditionProspex Sea 1968 Heritage Diver's GMTProspex Sea 1968 Heritage Diver's GMT WatchProspex Sea 1968 Heritage Diver's GMT Watch Limited EditionProspex Sea 1970 Heritage Diver's Black Series Limited EditionProspex Sea 1970 Heritage Diver's Save the Ocean Special EditionProspex Sea JAWS 50th Anniversary Limited EditionProspex Sea PADI Special EditionProspex Sea PADI Special EditionProspex Sea PADI Special EditionProspex Sea PADI Special EditionProspex Sea Save the Ocean Special EditionProspex Sea Save the Ocean Special EditionProspex Sea Save the Ocean Special EditionProspex Sea Seiko Diver’s Watch 60th Anniversary Limited EditionProspex Sea Seiko Diver’s Watch 60th Anniversary Limited EditionProspex Sea Seiko Prospex 1965 Heritage Diver’s Watch Save the Ocean Limited EditionProspex Sea The Black Series
Alternatives

01The living market

This one moves.

They are on r/Watchexchange and WatchUSeek right now, and finding them means searching both by hand. Not appraisals or offers.

Retail$550

2 for sale right now, and 1 closed in the last 90 days.

  • ·How long one takes to sell, from the listings that closed
  • ·All 2 listings, priced and linked
See what Lug2Lug Market+ adds

02The connection engine

More like this.

Seiko Prospex Sea Save the Ocean Special Edition

Seiko

Prospex Sea Save the Ocean Special Edition

42.4mm · Automatic$550

Seiko Prospex Sea PADI Special Edition

Seiko

Prospex Sea PADI Special Edition

45mm · Automatic$650

Borealis Watch Co. Estoril 300 GMT

Borealis Watch Co.

Estoril 300 GMT

41.5mm · Automatic$600

Phoibos Leviathan

Phoibos

Leviathan

40mm · Automatic$399

Tissot Seastar 1000

Tissot

Seastar 1000

40mm · Automatic$875

Marloe Watch Company Morar 310

Marloe Watch Company

Morar 310

42mm · Automatic$499

View all alternatives

03The community take

Owners talk.

“

Owners widely praise the Seiko Prospex Sea for its excellent value, robust build, and superb lume, with many noting its comfortable wearability. Reviewers consistently highlight its impressive finishing and classic dive watch design, often comparing it favorably to older models. Some owners find the size substantial, with one noting it as big, thick, and heavy on a 6.5-inch wrist, while others find it perfect. On balance, owners and reviewers rate the Seiko Prospex Sea highly for its exceptional value and robust, classic dive watch design.

Synthesized from 10 sources
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04The paper trail

05The discussion

Talk about the Seiko Monster.