09908 Pressure Cooker Sealing Ring/Automatic Air Vent Pack (3 & 4 Quart) Presto Pressure Cooker Sealing Ring. Presto Part Numbers 09908 9908 1758. 09908$8.89 For Models 603 *For U.S. Cookers Only* 60 (4-quart) 604 50 60 (2 1-2 quart)