How do the S and M sizes of the heavy canvas tote bag differ in their interior layout?

The heavy canvas tote bags from MATSUNOYA look alike on the outside, but differ in the features provided inside. Inside the S size, a key chain is attached so keys can be found and used right away, and inside the M size, a fastening belt is provided to keep items from scattering^[1][2]. Both bags are surrounded by five pockets on the outside and do not include a detachable shoulder strap, but the methods to support internal storage are divided differently according to size^[3][4].

This difference in layout aligns with the bag sizes and the nature of the items carried. The S size, with a width of 36.5cm, a width of 13cm, and a height of 25cm, is suitable for carrying belongings simply, making it useful to tether small keys so they are not lost^[5][6]. On the other hand, the M size, with a generous volume of 44cm in width, 17cm in width, and 29cm in height, allows you to maintain the bag's shape and balance by securing contents with a belt so they do not lean to one side when packing large items like thick books or clothing^[7][8].

hmmm, rather than simply increasing the outer dimensions, the bag features different mechanisms by considering the state of items that tend to shift around inside as the size grows.