A method for providing a product viewing window in a container, the method comprising: a. providing at least one container having a body, a first end, and a second end opposite the first end, wherein the container body comprises at least a body ply and a liner ply, and i. wherein the body ply has an inner surface and an outer surface and defines at least one aperture therethrough; and ii. wherein the liner ply is adhered to the inner surface of the body ply and has a portion extending across said aperture, forming a window into the container; b. providing a window-finishing machine that comprises: i. at least one first platen; ii. at least one second platen; iii. at least one machine pocket positioned between the at least one first and the at least one second platen, wherein the at least one machine pocket has an inside wall; iv. a heating element extending through the at least one first or the at least one second platen; and v. a pressurized air device that is adapted to release pressurized air into the container through the at least one first or the at least one second platen; c. engaging the first end of the container with the first platen and engaging the second end of the container with the second platen, wherein the engagement of the container is airtight; d. positioning the container window adjacent the inside wall of the machine pocket; e. positioning the heating element such that it is adapted to heat the window of the container, wherein the heating element is adjustable vertically or horizontally within the container such that the heat is directed toward the container window; f. heating the window of the container to the desired temperature; g. injecting pressurized air into the container such that the liner ply window is forced at least partially through the aperture of the container and into contact with the machine pocket wall; and h. allowing the container window to cool to the desired temperature. a. providing at least one container having a body, a first end, and a second end opposite the first end, wherein the container body comprises at least a body ply and a liner ply, and i. wherein the body ply has an inner surface and an outer surface and defines at least one aperture therethrough; and ii. wherein the liner ply is adhered to the inner surface of the body ply and has a portion extending across said aperture, forming a window into the container; i. wherein the body ply has an inner surface and an outer surface and defines at least one aperture therethrough; and ii. wherein the liner ply is adhered to the inner surface of the body ply and has a portion extending across said aperture, forming a window into the container; b. providing a window-finishing machine that comprises: i. at least one first platen; ii. at least one second platen; iii. at least one machine pocket positioned between the at least one first and the at least one second platen, wherein the at least one machine pocket has an inside wall; iv. a heating element extending through the at least one first or the at least one second platen; and v. a pressurized air device that is adapted to release pressurized air into the container through the at least one first or the at least one second platen; i. at least one first platen; ii. at least one second platen; iii. at least one machine pocket positioned between the at least one first and the at least one second platen, wherein the at least one machine pocket has an inside wall; iv. a heating element extending through the at least one first or the at least one second platen; and v. a pressurized air device that is adapted to release pressurized air into the container through the at least one first or the at least one second platen; c. engaging the first end of the container with the first platen and engaging the second end of the container with the second platen, wherein the engagement of the container is airtight; d. positioning the container window adjacent the inside wall of the machine pocket; e. positioning the heating element such that it is adapted to heat the window of the container, wherein the heating element is adjustable vertically or horizontally within the container such that the heat is directed toward the container window; f. heating the window of the container to the desired temperature; g. injecting pressurized air into the container such that the liner ply window is forced at least partially through the aperture of the container and into contact with the machine pocket wall; and h. allowing the container window to cool to the desired temperature.