Direct mail isn't dead nor is it dying. As part of doing everything you can to keep your own direct mail efforts alive and well, you must test. One of the key components to test is your carrier or outer envelope.Your outer envelope makes the first impression and helps your mailing stand out from the rest of the day's mail. It gets your piece past the person screening the mail - both at home and at the office. The envelope also gets your mailing opened and read.