Not a clue. Call them up. They can hook u up with the info you need.
A Google search takes one to Amazon, where a 3-pack for a Casio G Shock watch costs $5.91 + s/h.
@Jerry, thanks for the tip and I've successfully replaced watch batteries before on non-gshocks by myself but I broke 2 of my gshocks trying to replace their batteries so from on, I think i'll leave that to the experts.
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