THIS IS NOT FOR SELL THIS IS ONLY EDUCATION FOR FIRST CLASS MAIL

There been a lot of issue lately from customer and Mercari How to ship cards. What you see is an official USPS TEMPLATE for first class mail. In picture 2&3 you see how the first mail have to be able to slide through that little section. B/c all first class mail goes through a sorting machines which bends and moves the envelope. If the envelope is unable to go through the machine. The cards will come back to me and I get a note saying it need to be USPS ground or it need more postage. I list each cards as 3oz with is the largest size for usps first class mail for envelope, Mercari does not used flat first class mail. I ship my cards in penny sleeves with toplaoders or saver 1. NO I do not and will not ship the cards without any protection. I did that once for the request of the customer and the cards was destroyed. Lately Mercari has been messing up with the bundles how it should be mail So when I reach out to let you all know, the shipping is wrong b/c Mercari put the wrong shipping.