Quality Park 11 x 13.5 inch rigid mailers are built to stay flat to store large enclosures; made of 24 pt. paperboard with self seal flap; 25/box Please don’t lick these envelopes; Quality Park Redi-Strip closures don’t require moisture—just peel and press for a safe, dry, sanitary seal Peel-off strips protect adhesives from dust so your photo envelopes will last longer; stock up for bulk mail and events Rigid mailers are perfect for storing or mailing your prize photos, art prints or documents without bends or folds; mail with total peace of mind Hand address the glossy surface or speed your mail prep with customized address labels from your inkjet or laser printer