I usually send out a hundred Christmas cards and enclose a Christmas letter. I use "card-size" envelopes for this. However this year I was short on time. My husband and I decided to just send a letter. We moved this year and wanted our friends and family who did not have our new address yet to receive the address before they might send greetings to us. I stamped a simple design on each envelope to dress them up a bit. Two folds and the letter slipped easily inside. And the best part: pull off the strip from the flap fold over and swipe with a hand and it's done. No more licking the glue and hope it seals!