Legendary model! GA-400 series! Simple, refreshing monotone! Unique rotary switch! Purchased new at a certain mass retailer several years ago, but never used. However, the instruction manual and box are missing, so I'm listing it as "like new"! You can find the instruction manual on the Casio website by specifying Module No. 5398, which is engraved on the back cover! In excellent condition with no aging! The watch itself will be shipped via Yu-Packet Post, and changes are not possible! Even during transaction negotiations, I will unfortunately prioritize the first person to purchase! Thank you for your understanding... Thank you very much!