The gal at the post office explained to me when I questioned the amount of postage I was paying as opposed to some things that come thru with just a regular stamp. Regular stamp they go thru the stamping machine and that might be what is ripping them up. When I pay extra they are apparently hand stamped because everyone she put thru a cardboard holder with a slit in it and if it didn't fit, extra postage. I also received one that was handled by a pit bull but the plastic wrap kept the block intact. Amen