Crystal Clear Optical Clarity High quality material will not easily rip, tear, wrinkle, or fog Adhesive strip is on the body of the bag and does not come in contact with your product Fast insertion and sealing Acid and lignin free Archival safe Protective Closure bags are designed to prevent the adhesive strip from coming in contact with your product. The glue is on the body of the bag - not the flap Bag sizes indicates the opening side as the first dimension Bag dimensions have +/- 1/16' size tolerance