1. RESEALABLE SEALING STRIP - The mylar bags feature a sealing strip to keep water and moisture dust or any odors out when sealed, and the sealing strip is very tight, you will never question whether the mylar bags are open or closed. 2. LONG TIME FOOD STORAGE - The black mylar bag is polypropylene and foil material, means your food stay fresher for longer than a regular mylar bag. Mylar bags is suitable for packing, storing, shipping, sampling, and sorting. 3. PRACTICAL - This mylar bags for food storage can store coffee, beans, candy, sugar, rice, baking, cookies, tea, nuts, dried fruit, dried flowers, powder, snack, spices, and much more food or decorations. 4. HEAT-SEALABLE - The resealable mylar bags can heat sealable, double sided matte black heat seal bags. The mylar bags can work with various food sealer machines for extra protection.