Why Is It Effective? Adding a label to your envelopes can be a great way to get envelopes to stand out in the mailbox. Using a peel off label on a letter or response device can be used to encourage people to interact with your direct mail. Labels are a tried and true way to get people invested in their response. ​ Who Can Benefit? All mailers can benefit from some of our suggestions. Take a look at the samples we show and maybe you will get some ideas to test on your next cam