How to Vacuum Package Using the FoodSaver® Jar Sealer with Mason Jars Note: FoodSaver Jar Sealers can only be used with a FoodSaver® appliance that has an Accessory Port. Please check your QuickStart Guide to see if your machine has one. 1. P lace the FoodSaver ® appliance on a flat, dry surface and plug the power cord into a standard electrical outlet. 2. Place the item(s) to be vacuum packaged inside the Mason jar. Leave at least one inch (1”) between the contents and the rim of the jar. 3.