PostSeal is a quick and easy way to send letters, forms and documents from your mobile phone, tablet or computer. Let's simplify sending mail in a few steps: 1. Create letter files. PDF, JPG/JPEG and PNG files you would like to be posted in a letter via snail mail. 2. Upload the files. Simply drag and drop your files to PostSeal. 3. Fill in address details. Return and destination addresses. 4. Checkout. Confirm your purchase. 5. Relax. PostSeal will print, seal, stamp and send your letter.