From the USPS, November 22nd, 2016:
This new 2-ounce stamp is perfect for many of life special moments, as it can accommodate the weight of heavy invitations for birthdays, weddings, anniversaries, and other celebrations; oversize greeting cards for all occasions; and mailings such as small gifts that require extra postage. Celebration Corsage is similar in design to the Celebration Boutonniere Forever stamp, and the two form a natural pair. The corsage was arranged by floral designer Carol Caggiano and photographed by Renée Comet. Art director Ethel Kessler designed the stamp.