S-3440 Genuine Replacement Gasket for Mirro / Mirro Matic Pressure Canners. This gaskets fits Models M-312, M-312-35, M-406, M-416, M-512, M-512-11,  M-522, M-526, M-526-11, M-622. Made before January 1983.  If the canner was made after January 1983 you need to purchase a S-9882 Gasket. Identify the date stamp situated on the underside of your canner; it will be presented in a fractional format representing Month over Year.  In 2007, SEB Corp granted explicit authorization to Red Hill General Store for the procurement of Mirro / Mirro Matic pressure cooker components directly from the original manufacturer, as evidenced by the photograph. This is an Original Equipment Manufacturer Part produced in 2023.