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GA-2100 CasiOak Authenticity Check — 6 Tells That Still Work

The fake CasiOak got good. Six current tells for the GA-2100 — octagon geometry, carbon core, module 5637, lume, weight balance and LCD font — ranked by what still catches modern fakes.

GA-2100 CasiOak Authenticity Check

Tell 1

Octagon geometry

Genuine bezel: octagon sides have specific non-uniform flat-length ratios. Fakes get the shape but not the ratios — sides too equal, corners too soft or sharp. Compare a straight-on photo against official images.

Tell 2

Carbon core texture

Genuine resin carries the carbon fiber core — a subtle marbled texture visible on the caseback inner ring and strap keeper undersides. Fakes: plain resin or a printed carbon-look decal that reads flat under magnification.

Tell 3

Module number depth

5637 is correct for the GA-2100 family. Newer fakes know the number — so check engraving depth and the font of surrounding text, not just the digits.

Tell 4

Lume application

Genuine applied indexes carry even lume dots. Fakes: uneven application — one dot brighter or fatter than its neighbors, obvious under UV or in the dark.

Two more checks, and an honest warning

Display font: LCD segment edges and digit stroke weights come from tooling counterfeiters don't re-engineer. Genuine strokes are consistent; fakes show thick-thin inconsistency, especially on the "1".

Weight balance: genuine ~51 g with even balance across case and strap. Modern fakes add weight to pass the hand test — but often only in the case, leaving the strap feeling hollow. Weak as a standalone check, useful in a side-by-side.

The honest warning: the fake CasiOak improved fast. First-generation fakes fooled nobody; current ones pass photos and survive one or two classic checks. The octagon geometry (tell 1) and display font still catch most current units — but no single check is enough. Run the full battery, and treat any single pass as worth nothing.

Photo checklist for remote verification

If you're verifying a unit remotely (marketplace purchase, pre-shipment photos from a supplier), request three shots: caseback close-up, straight-on bezel shot, and the display lit in a dim room. Those three angles cover the tells that still work from photos — 1, 3 and the display font.

More verification guides

F-91W — 4-point check DW-5600 — 4 checks Universal — 4 layers Fake quality tiers Bulk QC — AQL & receiving

Buying stock and want it verified before shipping?

Every JOJO WATCH WHOLESALE order ships with model-labelled cartons, packing lists and pre-shipment photos — verified with exactly the checks in this guide.

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