Get the Envelope Opened!
However, the majority of efforts in the mailstream are window envelopes. What you have peeking out of the envelope's window can be used to cause some excitement, such as the faux check. Omaha Steaks has used this approach with success for many years. With the words, "Your Reply Will Really Be Appreciated!" as the headline on a #10 white envelope, a fake check peeks through the window. Inside, the recipient sees that it is good for a discount on steaks. Who can resist opening an envelope with a check showing through?
If you use one window, why not use two? A control from Science News uses a second window, shaped in a circle, to show the word "Free" peeking through. Dudley has seen mailers test and roll-out double windows, so with the right offer, they can be effective. Another window feature that mailers use is a panoramic window, which usually covers the whole face of the envelope. Although he has seen a fair number of these tested, Dudley comments that not as many of these seem to roll-out. "The expense of a panoramic window can be a deterrent...among all the ways to differentiate your package, it's probably the most expensive."
In direct mail, size does matter. If everyone is mailing #10 envelopes, a different size can create some attention. A larger sized, 9˝x12˝envelope was employed successfully by the Harvard Heart Letter for a number of years. The 9˝x12˝ format has also been used by other magazines—namely, Smithsonian, Popular Science and Golf. All three have used this format, along with stickers on the OSE, to involve the reader and entice them inside the mailing.
But the 9˝x12˝ isn't the only option under the sun. Other possibilities include a 6˝x9˝, # 9, #11, etc. According to Dudley, popular sizes include the 9˝x12˝, 83⁄4˝ x113⁄4˝ and the 61⁄8˝x111⁄2˝. The 61⁄8˝x111⁄2˝ size has additional value, because it is large enough to stand out in a sea of #10s, but still qualifies for the letter rate postal discounts.