FSC? certification has become one of the most recognisable environmental credentials of the day. These envelopes are made from FSC? certified paper and clearly promote the FSC? logo and credentials through the window of the envelope. Its obvious advantage being the extended shelf life that comes with peel and seal and is becoming more and more popular due to this key feature. These envelopes have a handy gummed closure for quick and easy fastening. They are wallet opening; meaning that they open along their longer side for quicker access.