You cannot send a clothing pattern first class with delivery confirmation unless its at least one fourth in thick, and not more than three fourths in thick. If it doesnt meet this requirement, the post office will change it to Priority mail, and charge your buyer an additional 3.00 plus dollars to get it. That will not encourage your buyer to leave 5 stars on shipping. So, either leave off delivery confirmation, or add tissue, cardboard, or bubble wrap to the pattern envelope to make it at least one fourth inch thick. Ive had to pay an additional 7 dollars for two patterns just in the last week. It seems insane to charge more because an item isnt big enough, but thats the USPS for you. Update- I posted about this problem in Ebay discussion groups, and it appears the sellers there knew about the first class with delivery confirmation requirement. Except they are saying the envelope must be three fourths inches thick. Either way, Im already out 7 dollars, and theres more patterns coming. I cant very well leave 5 stars on shipping, and good feedback when Im having to pay over double what Ive already paid for shipping because the patterns werent mailed correctly.