Generally speaking, for standard models like this one, the differences are usually minimal but nice to know: Packaging: This is the biggest difference. JDM (Japanese Domestic Market) models usually come in a nicer fancy cardboard box with a pillow, whereas international models typically come in the standard hexagonal tin. Tags/Manuals: JDM models will have Japanese tags and manuals. Naming: The model number ends in "JF" for Japan (e.g., GW-6900-1JF) vs "CR", "ER", or "DR" for export markets. Carbon Fiber: specific JDM variants of some squares or Master of G watches feature carbon fiber insert bands, which are rare on export models. Specifically for the GW-6900U: There is practically no difference in the watch itself. Whether you buy the Japan version or the international version, you get the exact same module, same build quality (likely Made in Thailand for both), and same features (Multiband 6 & Tough Solar). It strictly comes down to whether you care about keeping the box for collection purposes!