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Casio watch · digital module

Casio G-7900 manual and battery (CR2025)

Casio's operation guide for the Casio G-7900 is the PDF for module 3194: Casio operation guide 3194 (PDF) ↗. It takes a CR2025 battery. The case is 50 mm wide, 52.4 mm long (case length L, not lug to lug), and 17.7 mm thick.

Sources checked · How we source numbers
Width (W)
50 mm1
Case length (L)
52.4 mm1
not lug to lug
Thickness
17.7 mm1
Lug width
not published by Casio
Casio G-7900: size drawingCasio G-7900, rect case, top and side view to scale: case width 50 mm, case length (Casio L) 52.4 mm, lug width — (unknown), thickness 17.7 mm. Bezel, dial and crown size are schematic.lug width —width 50case length (Casio L) 52.4TOPthickness 17.7SIDE
Casio G-7900, top and side, to scaleDrawing from data, not a photo · mm

Module 3194 twins

Casio's manual list puts 10 model codes on this module: same functions, same manual, often the same battery.

Codes of the Casio G-7900 family[3]G-7900, G-7900A, G-7900MS, G-7900RF, G-7900SLG

5 more codes on the same module

GLX-6900, GLX-6900A, GLX-6900SS, GLX-6900X, GLX-6900XA

Casio module 3194: functions, battery and manual

Module: Casio module 3194

The Casio G-7900 runs on the Casio module 3194, a digital module.

Power source
battery2
Battery life
2 years2
Accuracy
±15 s/month2
Light
EL (electro-luminescent panel); selectable illumination duration; Auto Light Switch2

Battery

Casio G-7900 specifications

Case width (W)
50 mm1
Lug to lug
not published by Casio; see case length (L)
Case length (L)
52.4 mm1Casio's L of L × W × H, measured differently from lug to lug; we never swap one for the other.
Thickness (H)
17.7 mm1
Lug width
not published by Casio
Weight
68.2 g1
Crystal
Mineral Glass1
Water resistance
200 m1
Module
Casio module 31943 · digital moduleCasio module 3194 specs
Battery
Accuracy
±15 s/month1
Years made
start not published
Case code
not used by Casio: the module number (module 3194) identifies the watch

On your wrist

The verdict compares the case length (L) with the flat top of your wrist. Balanced from ~18.5 cm, past the edges below ~16.5 cm.

= 6.7 in

At the edge on a 17 cm wrist: the 52.4 mm case length (L) covers 96% of an estimated 54.8 mm flat top.

Casio publishes no lug-to-lug for this model, so the verdict uses its case length (L). The strap or bracelet joins inside that length, which makes this a cautious estimate.

Flat top = circumference ÷ 3.1, a community convention, not a measurement of your arm. Compact ≤ 0.75 of the flat top, balanced ≤ 0.89, at the edge ≤ 1. Compare more watches in the watch size calculator.

Casio G-7900: wrist fitCasio G-7900 on a wrist, top view to scale. case length (Casio L) 52.4 mm. Wrist 170 mm, estimated flat width 54.8 mm (circumference / 3.1). Ratio 0.96: at the edge.wrist, flat topwrist flat ≈ 54.8case length (Casio L) 52.4At the edge · 52.4 / 54.8 = 0.96estimate: wrist 170 / 3.1 = 54.8 flatcompactbalancededgeoverhang0.750.891
Casio G-7900 on a 17 cm wristDrawing from data, not a photo · mm

Actual size on your screen

Calibrate once with a bank card and the drawing shows the Casio G-7900 at 1:1, next to a millimetre ruler.

1:1 · not calibrated: sizes are approximate
Casio G-7900: size drawingCasio G-7900, rect case, top and side view to scale: case width 50 mm, case length (Casio L) 52.4 mm, lug width — (unknown), thickness 17.7 mm. Bezel, dial and crown size are schematic.lug width —width 50case length (Casio L) 52.4TOPthickness 17.7SIDE
Drawing from data, not a photo · mm
01020304050

Casio G-7900 strap size

Casio publishes no lug width for the Casio G-7900. Measure between the lugs with a caliper before buying a third-party strap.

Attachment: not published in our sources.

Find your strap length in the watch strap size tool, with the Casio G-7900 filled in.

Same size as the Casio G-7900

The models nearest to the Casio G-7900 in case width and case length (L), drawn over it to scale; below, every model within 1 mm of its 52.4 mm.

Size comparison: Casio G-7900, Casio DW-6900, Casio GD-350, Casio HDC-700Top-view outlines to scale on one centre. A Casio G-7900: W 50, L 52.4, lug —, T 17.7. B Casio DW-6900: W 50, L 53.2, lug —, T 18.7 (vs A: W 0 L +0.8 T +1). C Casio GD-350: W 50.8, L 53.4, lug —, T 18 (vs A: W +0.8 L +1 T +0.3). D Casio HDC-700: W 48.8, L 53.3, lug —, T 16.6 (vs A: W −1.2 L +0.9 T −1.1).D W 48.8A W 50B W 50C W 50.8A L 52.4B L 53.2D L 53.3C L 53.4A Casio G-7900W 50 · L 52.4 · lug — · T 17.7B Casio DW-6900W 50 · L 53.2 · lug — · T 18.7vs A: W 0 L +0.8 T +1C Casio GD-350W 50.8 · L 53.4 · lug — · T 18vs A: W +0.8 L +1 T +0.3D Casio HDC-700W 48.8 · L 53.3 · lug — · T 16.6vs A: W −1.2 L +0.9 T −1.1
A Casio G-7900 and the 3 nearest in size, on one centre, to scaleDrawing from data, not a photo · mm

Nearest in size

  1. ACasio G-7900this watch
  2. BCasio DW-6900W same · L +0.8 · T +1 mm
  3. CCasio GD-350W +0.8 · L +1 · T +0.3 mm
  4. DCasio HDC-700W −1.2 · L +0.9 · T −1.1 mm

Differences against A in mm: W case width, L Casio case length, T thickness. Nearest by width and length together, from the published sizes.

Same published case dimensions (1)Casio GW-7900

Casio G-7900 questions

Where is the manual for the Casio G-7900?

The Casio G-7900 runs Casio module 3194, and Casio publishes the operation guide for that module as a PDF: Casio operation guide 3194. The module number is stamped on the case back. All of the module’s models and its battery are on its page.

What battery does the Casio G-7900 take?

The Casio G-7900 takes CR2025, rated about 2 years.

How big is the Casio G-7900?

The Casio G-7900 measures 50 mm wide, 52.4 mm long (Casio's L, not lug to lug), 17.7 mm thick, 68.2 g.

Will the Casio G-7900 fit a 7.5-inch wrist?

Balanced: the Casio G-7900's 52.4 mm case length (L) takes 85% of the ~61.5 mm flat top of a 7.5-inch (19.1 cm) wrist. By the same estimate (circumference ÷ 3.1) it sits balanced from about 18.5 cm and overhangs the flat top on wrists under about 16.5 cm.

What module is in the Casio G-7900?

The Casio G-7900 runs on the Casio module 3194, a digital module. Casio's manual list puts 10 model codes on this module, 5 of them G-7900 codes.

More Casio watches

Sources

Documents checked · Report a wrong number

  1. 1Casio America — G7900-1 | Digital Black Men's Watch G-SHOCK | CASIO (product page) · html · read
  2. 2Casio Computer Co., Ltd. — Operation Guide 3194 (qw3194_EN.pdf) · pdf · read
  3. 3Casio Computer Co., Ltd. — Watch manual search JSON (US locale), manual_search.support.json · json · read