Technical Archive

Casio
G-Shock GA-100 GA-100-A9

Casio G-Shock GA-100 GA-100-A9: strap made to measure on the watch at the Casati Milano atelier, by appointment.

Reference

GA-100-A9

Movement

Casio caliber 5081 World Time | Perpetual Calendar | Chronograph, Countdown | Alarm

The Heritage

The GA-100A-9A Bumblebee is a G-Shock model featuring a 55mm resin case designed for extreme durability. This iconic timepiece combines Casio's robust engineering heritage with contemporary street style. Milano Straps offers custom-fitted straps developed by Atelier Casati Milano, including Tuscan vegetable-tanned leather and premium NATO options tailored to the watch's integrated lug geometry.

Made to Measure

The strap for this watch is made to measure

On the Casio G-Shock GA-100 the bracelet is drawn as part of the case: no catalogue strap will fit. In the atelier we take the measurements on the watch itself and build the strap on the piece — that is the work of Casati Milano.

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FAQ

Can I attach a standard strap to the Casio G-Shock GA-100 GA-100-A9?

No, the bracelet is integrated into the case and the attachment is proprietary — a standard strap won't fit. That's where we come in: I craft a bespoke strap directly on your case geometry, with no shortcuts.

How does the bespoke strap work for the GA-100?

We work by appointment only at <a href="/pages/casati-booking">Casati Milano</a>, Via XX Settembre 15 in Milan. I take measurements directly from your watch case, develop the custom interface, and build the millimetric strap. It's the only way I know to do it properly.

Which leather do you recommend for the G-Shock GA-100?

I prefer vegetable-tanned Tuscan leather: it ages with character, developing a patina that reflects the military-sport soul of this watch. If you want something more contemporary and sustainable, premium NATO in regenerated yarns enhances the technical ethics of the G-Shock without sacrificing elegance.

How long does a well-made strap last?

With active use, a handcrafted strap lasts 4-6 years, sometimes longer. It depends on your exposure and how you care for it — vegetable leathers dislike water stagnation. If you dry it properly and treat it with respect, it'll follow you for years and age better than you'd expect.

Why does the G-Shock GA-100 deserve a bespoke strap?

Born in 1983 as a symbol of extreme durability — 10 metres of free fall, 10 bar pressure resistance. The GA-100 brings this philosophy in 55mm of pure attitude. Replacing the integrated bracelet with a custom strap isn't compromise: it's respect for the engineering on your wrist and your personal taste.