Grip 'n Seal Technology: Unbeatable freezer protection (Compared to other freezer seal top bags). Microwave safe. Strong enough to use again. Fill, use, repeat. A family company since 1886. - Fisk Johnson. Defrost & reheat - vent bag 1 inch. Environmental Facts: Bags are recyclable when clean and dry at drop-off bins at participating retailers. Please recycle this paperboard carton.