Side by side

Casio GBM-2100AvsMomentum M20 GMT

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

GBM-2100A
CasioGBM-2100A
MSRP $280
M20 GMT
MomentumM20 GMT
MSRP $315
What people say

Owners + reviewers, side by side

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

Casio GBM-2100A

The premium stainless steel bezel and Bluetooth connectivity are highlighted strengths. The increased mass from the metal bezel is noted as a potential drawback for some wearers. Reviewers differ on its value proposition compared to other G-Shock models.

Momentum M20 GMT

Owners widely praise the Momentum M20 GMT for its robust build quality, featuring 216L steel and a sapphire crystal, along with a satisfying 120-click bezel action. The GMT function is noted for its utility, enhanced by numerals on the rehaut. The 42mm case is reported to wear comfortably like a 40mm due to curved lugs, and the heavy-duty bracelet is considered exceptionally comfortable and superior to aftermarket options. Some owners note the second hand occasionally misses markers, and one opinion compares it unfavorably to Seiko. Overall, owners rate the Momentum M20 GMT highly for its durable tool watch construction and comfortable wearability at its price point.

At a glance

13 of 29 specs differ
Diameter
GBM-2100A44.4mm
M20 GMT42mm
Power Reserve
GBM-2100A
M20 GMT
Water Resistance
GBM-2100A200m
M20 GMT200m
MSRP
GBM-2100A$280
M20 GMT$315

Full specifications

Case

7 specs
Category
Sport
Diameter
44.4mm
42mm
Thickness
11.9mm
13mm
Lug-to-Lug
49.3mm
50mm
Lug Width
22mm
Material
Bio-based Resin / Stainless steel
Stainless Steel
Finish

Crystal & Dial

3 specs
Crystal
Mineral
Sapphire
AR Coating
No
Dial Color
Silver

Movement

2 specs
Caliber
Ronda 515
Power Reserve
0h

Pricing

1 specs
MSRP
$280
$315
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