The size chart of this style is as follows:

----US Size-----:----Label Size-----Inside Length---

----5.5 M US----:------36------------- 23 cm ---------

----6 M US------:------37------------- 23.5 cm -------

----7 M US------:------38------------- 24 cm --------

----7.5 M US----:------39------------- 24.5 cm--------

----8 M US ----:------40------------- 25 cm ---------

this one is a normal size. It is suggested to take a size larger if the feet are wide or fat.