ARY VacMaster 30791 7 x 12 Chamber Vacuum Packaging Pouches . . . These 7" x 12" industrial strength, 3 mil chamber vacuum packaging bags help keep food fresh up to five times longer than traditional storage methods! The chamber pouches seal securely with any chamber vacuum packaging machine to ensure long lasting freshness Made of 80% polyethylene and 20% nylon, these pouches can be frozen, refrigerated and even microwaved with resistance to puncture and