This indicates the credentials in the list are specifically targeted at email accounts.
The file you are referencing, "900K HQ COMBO MAIL ACCESS TARGET," is a , which is a collection of stolen usernames and passwords. These files are primarily used by cybercriminals to perform automated attacks. What This File Is Download File 900K HQ COMBO MAIL ACCESS TARGET ...
Downloading or attempting to use these files carries severe risks: This indicates the credentials in the list are
Combolists and ULP Files on the Dark Web: A Secondary ... - Group-IB "900K HQ COMBO MAIL ACCESS TARGET