Build a US Letter PDF with one centered 6 x 4 postcard, a traditional address side, and a dotted cut guide for trimming after printing.
Printed on the message side of the postcard.
Required. Printed in the mailing area on the right half.
Optional. If left blank, the message area expands to use the extra space.
Mirrors only the message text, making it less readable at a glance. A mirror will make it readable normally.