When using member to member transfers, what is an account suffix?

It’s a piece of information that identifies the exact account.  For example, checking, savings, auto loan, etc.

The transfer recipient can find that number in two places

• In the mobile app, the suffix is found next to the account name on the Accounts page. It is the number to the right of the dash. 
• In online banking, the suffix is found on the My Accounts section of the landing page. It is the number to the right of the dash.