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Casio W-800h Mod Info

Casio W-800H Go to product viewer dialog for this item. is widely regarded as one of the most versatile "blank canvases" in the watch-modding community. Its combination of a large, clear display and a module shared with more expensive models makes it a prime candidate for unlocking hidden features and visual overhauls. Unlocking the Hidden Countdown Timer The most popular electronic modification for the involves activating its factory-disabled countdown timer. The Hardware Hack: The

uses module 3240, which shares a PCB with models that include more features. By removing a specific solder jumper on the circuit board, you can enable a 24-hour countdown timer. The Process: Open the case back and remove the module.

Locate the specific solder bridge (jumper) on the back of the PCB. casio w-800h mod

Use a soldering iron and copper wick to desolder and remove the lead bridge. Short the "AC" contact to the battery to reset the module.

Bonus Feature: Some users have discovered that pressing the Light button while in the timer setting mode toggles an "auto-repeat" function, though there is no visual indicator on the screen for this. Visual and Display Modifications Beyond feature unlocks, the Casio W-800H Go to product viewer dialog for this item

is frequently customized to improve legibility or aesthetics. YouTube·Greg Anderson - The Good Timekeeper

Mod #2: The Strap Swap (NATO, Adapters, & Silicone)

Difficulty: 1/10 | Cost: $10 - $30 The stock resin strap of the W-800H is stiff and dust-magnetic. Fortunately, the lug width is 18mm (though the gap is tight). Mod #2: The Strap Swap (NATO, Adapters, &

JaysAndKays Adapters: The gold standard. These metal adapters fill the resin gap and allow you to use standard 18mm spring bars for NATO straps.
The Nato Look: A Bond-style NATO or a solid gray Marine Nationale strap elevates the watch immediately. It removes the "plastic toy" feel.
Warning: Do not use curved spring bars; use heavy-duty straight 18mm bars.

1. The “Hydro Mod” (Most Popular)

The W-800H’s crystal is recessed, making it prone to smudges and glare. The fix? Fill the case with silicone oil (low viscosity, like 5cSt or 10cSt). This eliminates internal reflections, makes the LCD “pop” as if painted on the glass, and increases water resistance dramatically (theoretically past 200m). The downside? The buttons become stiff, and it’s messy if you fail.

4. Hydromod & Altitude

If you hydromod your watch and then fly on a plane, the liquid expands. Some users report button failure at altitude. If you travel frequently, skip the oil fill.