This is a very popular envelope for non-profits, charities, churches or any type of fundraising group. It is sometimes referred to as a 6 ¾ donation/return envelope. The 6 ¾ envelope is commonly used as an insert into booklets or newsletters when an organization is looking for a donation. They are also popular choice to use in political mail campaigns as an addition to an information pack. They are usually self-addressed so the end user would write out their check and mail it back to the organizer. 6 3/4 returns tend to be ordered in bulk. These envelopes are inkjet and laser printer safe.