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 --------
----8.5 M US-----:------41------------- 25.5 cm ------
----9 M US -----:------42------------- 26 cm ---------
----10 M US-----:------43------------ 26.5 cm ------
----10.5 M US-----:----44------------- 27 cm ----------
This one is a normal size. It is suggested to take a size larger if the feet are wide or fat