High Density Freezer Storage Bags are made from High Molecular, High Density (HMHD) polyethylene.  This extremely durable and flexible material allows our food storage bags to be frozen to -50°F and then heated up to 220°F.  This allows food to be taken directly from the freezer to microwave or boiling water, steamers, or warmers without freezer burn and without the need to repackage or transfer foods.  Additional benefits include grease and leak resistant, moisture vapor barrier prevents foods from drying out, prolongs shelf life in freezers, coolers and warmers.