These polyester folders are sealed along one long side and feature 1 inch flaps on the opposite side. Please note that the smaller sizes through 8 x 10 are offered in .003, and the larger sizes, from letter size up, are available in .004 in. archival polyester. As with all of our products, if you do not see the size you need, please contact us with your details. We will be happy to assist you. Packages of 10.