Priority Mail Priority Mail — One Large Book (Such as 8 1/2″ by 11″) Priority Mail — Two Large Books (Such as 8 1/2″ by 11″) Priority Mail — Flat Rate Box (Up to 10 books) Share this: Share on X (Opens in new window) X Share on Facebook (Opens in new window) Facebook Share on LinkedIn (Opens in new window) LinkedIn Share on Reddit (Opens in new window) Reddit Share on Tumblr (Opens in new window) Tumblr Share on Pinterest (Opens in new window) Pinterest Email a link to a friend (Opens in new window) Email