Made from quality archival polyester and acid-free paper, the Lineco® mounting strips offer efficient hinge-less mounting of artwork onto mats. With a self-adhesive backing strip, they provide a firm and strong stick. Easy to use, these See-Thru archival mounting strips attach to the backer board of mats holding the photo. They give support to your print or photos without letting the adhesive come in contact with the art. This pack comes with 60 mounting strips of 4 inch each.