Why are both Japan and Thailand listed together in the country of origin labeling?

When looking at the product packaging or detailed information, you will encounter two country names in the country of origin labeling. It takes the form of adding "Leather: Thailand" in parentheses next to the country name "Japan."

TRAVELER'S COMPANY's TRAVELER'S notebook has a structure where a paper notebook is inserted into a cowhide cover^[1]. The two components—the leather that wraps the outside and the paper that takes writing on the inside—are made in different countries. For both the Regular and Passport sizes, the outer cowhide cover is manufactured in Thailand^[2][3]. On the other hand, for the blank MD paper refill notebook that fills the inside, everything from paper production to saddle-stitch binding is completed in Japan^[4].

Because the points of origin for the inner pages holding records and the cover protecting them are different from each other, the names of two countries came to remain side by side on a single country of origin label^[5].