Casio F-91W — Metal Case Kits & Straps

The F-91W is a $20 legend, and modding it is the community's favorite running joke that went mainstream: stainless case kits, titanium shells, and straps that turn the "beater" into a conversation piece. Our kits ship with gasket and buckle included — the full glow-up in one box.

Fitment chart

Model Lug / Mount Adapter
F-91W / A158 / A159 / W-218 Proprietary (kit-specific) Use kit straps or listed companions

Quick answers

Does the metal case keep the F-91W water resistant?

Kits include a fresh gasket; seated correctly, splash resistance is maintained. The module itself is factory-rated only for everyday splash.

Is installation difficult?

It is the classic first Casio mod: open the resin, seat the module in the metal shell, close. Budget 15 minutes and follow the included guide.

Steel or titanium case?

Steel for weight and shine, titanium for the featherweight feel and matte gray finish — the community favorite for full builds.

Aftermarket accessory. Not affiliated with Casio, Apple or any brand mentioned. All trademarks belong to their owners.