How big can a paper made envelope be? The answer is really huge, but any large measurement must be settled according to the users' requests of the specific dimension. The X-Ray Film Kraft Paper Envelope we manufacture is the symbol of the functional envelopes that are widely used in some medical organizations. Reaching the 17 1/4" x 14 1/2" measurement requires adequate paper thickness, which can achieve the aims of huge measurement, strong structure, reasonable stiffness, and high quality. Therefore, we chose 100 grams per square meter Ribble manila paper as the basic paper material, and we don't use 80 grams per square meter paper to manufacture the 368x444mm white paper envelope or manila paper envelope at all, to make sure the security function won't miss for this measurement.