login/min_password_specials is a SAP Parameter attribute which is used to control min. number of special characters in passwords information. This is available within R/3 SAP systems depending on the version and release level.
Below is the standard documentation available and a few details of the attributes values .
This parameter specifies the minimum number of special characters that a
password must contain. It applies both when assigning new passwords and
when changing the password or resetting passwords.
All characters are special characters that
are not digits (0-9)
are not the ASCII letters A-Z or a-z. These include national special
characters and Unicode characters (if you are working in a Unicode
system), as well as the ASCII characters
See SAP Parameter Documentation for full SAP documentation for this profile parameter.