This is the Casio Mod.Club. In no way affiliated to Casio. It's the one stop shop for modded Casio F-91W. Introduced in 1991, it has been a reliably, simple unpretentious watch.

Modded watches available here offer a diverse selection of modifications to the watch face and external functionality not offered before. These mods are created by others and myself.

Internal modification changes the water resistance so it is best to keep it way from direct moisture ingress. Battery life can last up to 10 years on spare use.

The original F-91W.

Available Modifications:

LED Color + Brigthness:
Red, Green, Blue, Orange, Pink, Purple
Added Communications Technology
SD Card Holder
Store an Micro SD Card on your wrist
Watch Face
Modded to your wishes.
Transparant / Inverted
LCD Polarizer/Backplane removal
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NFC Chip behind the watch face.

The F-91W in parts.

NFC Chip + Custom White LED.

A black watch face on the F-91W.

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Regular watch face graphic (no black or others).
Additional options available: LED Color / NFC Chip / SD Card Holder.

Prices are excluding tax (Calculated by Paypal checkout).
You'll be ordering through the safe PayPal environment.


Lead time is a month. Feel like reaching out?
Need help figuring something out? Let me know at casio[at]


Curious what all those options are?
Here's a showcase that should give you an idea of what you are getting into.

The original F-91W + Orange LED.

Black watchface + Orange LED.

Black watchface + Blue LED.

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