Side by side

Phoibos Reef MastervsSeiko Monster

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

Reef Master
PhoibosReef Master
MSRP $335
Monster
SeikoMonster
MSRP $550

At a glance

12 of 29 specs differ
Diameter
Reef Master42mm
Monster42.4mm
Power Reserve
Reef Master40h
Monster41h
Water Resistance
Reef Master200m
Monster200m
MSRP
Reef Master$335
Monster$550

Full specifications

Case

4 specs
Diameter
42mm
42.4mm
Thickness
13mm
13.4mm
Lug-to-Lug
48mm
49.4mm
Lug Width
22mm
20mm

Crystal & Dial

4 specs
Crystal
Sapphire
Hardlex
AR Coating
Yes
Inner
Dial Color
Green
Black
Lume
Super-LumiNova
LumiBrite on hands, index(es) and bezel

Movement

3 specs
Caliber
SII NH38
4R36
Power Reserve
40h
41h
Jewels
25
24

Pricing

1 specs
MSRP
$335
$550

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What people say

Owners + reviewers, side by side

Synthesized for each watch independently from owner discussions, enthusiast forums, written reviews, and video reviewers.

Phoibos Reef Master

Owners widely praise the Phoibos Reef Master for its exceptional value, highlighting its sapphire crystal, DLC coating, and extensive BGW9 lume. The watch is noted for its cool lume, with one owner finding it not bulky despite its robust build. The Shamrock Green dial and texture are highly praised, as is the comfortable bracelet with solid end links. However, the bezel action is described as rough, and the basic folding clasp is a disappointment. Accuracy is reported as excellent, with one owner seeing +-2 sec/day. Some find the 42mm size almost too big for their wrists, and the date window is considered too small. Overall, owners rate the Phoibos Reef Master highly for its impressive feature set and value at its price point.

Seiko Monster

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.

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