Merkur Monoblock TunavsSeiko Monster

lug2lug doesn't sell watches. Buy links open the brand's or seller's own site. Some links are affiliate links: lug2lug may earn a commission at no extra cost to you. Disclosures

Measurements

Catalog photos are all shot at the same flattering size. These aren't: every case below shares one millimeter scale.

Merkur Monoblock Tuna at true scale

Monoblock Tuna

Seiko Monster at true scale

Monster

Diameter

47mm

42.4mm

Lug-to-Lug

48mm

lowest

49.4mm

Thickness

17mm

13.4mm

lowest

Water Resistance

200m

200m

Power Reserve

40h

41h

highest

MSRP

$279

lowest

$550

Movement

Seiko NH35

Seiko 4R36

Case

3 specs
Diameter
47mm
42.4mm
Thickness
17mm
13.4mm
Lug-to-Lug
48mm
49.4mm

Crystal & Dial

2 specs
Crystal
Sapphire
Hardlex
Lume
None
LumiBrite on hands, index(es) and bezel

Movement

3 specs
Caliber
Seiko NH35
Seiko 4R36
Power Reserve
40h
41h
Jewels
0
24

Pricing

1 specs
MSRP
$279
$550
Keep your wishlist and collection together in the appExplore the app

Reviews

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

Merkur Monoblock Tuna

Merkur MONOBLOCK TUNA owners widely praise its excellent finishing, often noting it surpasses typical examples, and appreciate the tactile, satisfying 60-click bezel action on the titanium case. The watch is described as robust, handling snow exposure and submersion well, with reliable performance and accuracy around +2 to +3 seconds per day. Some owners highlight the monoblock case construction and sapphire bezel insert options, while others enjoy the beautiful color and killer styling on an oyster bracelet. The quality is considered surprisingly good for the price. On balance, owners rate the Merkur MONOBLOCK TUNA highly for its exceptional finishing and reliable performance at its price point.

Seiko Monster

Owners widely praise the Seiko Monster for its superb lume and comfortable wearability, with reviewers noting its robust build and excellent value. The bezel action is described as smoother and more precise than some alternatives, and the inclusion of drilled lugs is a functional benefit. One owner found the 42.4mm case size perfect, while another with smaller wrists felt it was substantial. Overall, owners and reviewers rate the Seiko Monster highly for its exceptional value and reliable dive watch performance.