For a $16 pledge, you'll get a copy of the book at 99 cents off the retail price, and your name will be printed on the acknowledgments page. Free shipping within the United States. $18 shipping to Canada and Mexico. $24 shipping to the rest of the world.
(Beginning January 21, 2018, the United States Postal Service no longer allowed books to be mailed to other countries as First-Class International Large Envelopes. They now have to be shipped as parcels which is significantly more expensive.)