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Home/Browse/Casio/B640
Casio B640 — Black
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Casio B640

Ref. B640
Sport
A100
A130
A140
A158
A159
A168
A171
A700
AE-1000W
AE-1200WH
AE-1300WH
AE-1500WH
AE-1600H
AEQ-110W
AQ-230
AQ-240
AQ-S810W
AQ-S820W
AW-80
B640
B650
CA-53W
DBC-32
F-108WH
F-201WA
F-91W
LA670
LA680
MDV-106 Duro
MQ-24
MRW-200H
MTP-VD01
STR-300
W-218H
W-735H
W-738H
W-800H
W-96H
3 Variants
Buy from Casio ↗
Buy used on eBay ↗
Retail MSRP
$80
Low
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Avg
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High
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Static data
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Alternatives
Case
35mm
Power Reserve
—
Movement
Quartz
Water Resistance
50m
Crystal
Acrylic
01

Case Dimensions

Diameter35mm
Thickness9.4mm
Lug-to-Lug38.9mm
Lug Width—
02

Case Build

MaterialResin
Water Resistance50m
03

Crystal & Dial

CrystalAcrylic
Dial ColorBlack
04

Movement

TypeQuartz
Beat Rate—
Power Reserve—
Jewels—
HackingNo
Hand-WindingNo
ComplicationsTime only
05

Design Language

Case shapeRectangular
Dial styleMatte
BezelFixed
Bracelet / strapLug-attached bracelet
HandsBaton
AI-detected from product image · 7/3/2026
In a nutshell

The Casio B640 (ref. B640) is a quartz sport watch, with a 35mm resin case, 9.4mm thick. Water resistance is rated to 50m, under a acrylic crystal. Manufacturer MSRP is $80.

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