How many tabs minimum are required for a letter-size folded self-mailer?

For a letter-size folded self-mailer, the requirement is a minimum of two tabs. This specification ensures that the self-mailer is securely sealed at both ends, which is essential for proper handling and delivery through the mail system. The use of two tabs helps to maintain the structural integrity of the mail piece, reducing the likelihood of it opening during transit. This requirement aligns with postal regulations intended to facilitate efficient processing and minimize the risk of damage or loss. In certain scenarios, additional tabs may be used for extra security, but at a minimum, two tabs are necessary for compliance.