The mylar bags feature a sealing strip zipper closure to keep water, moisture, dust, and odors out when sealed. The sealing strip is secure, ensuring you will never question whether the mylar bags are open or closed. The smell-proof bags are made of mylar and foil material, helping your food stay fresher longer than in a regular zipper closure bag. Mylar bags are suitable for packing, storing, sampling, and sorting. These resealable bags can store coffee, beans, sugar, rice, baking ingredients, cookies, tea, nuts, dried fruit, dried flowers, medicine, herbs, spices, and many other foods or dry goods. The mylar bags are heat sealable, with double-sided black heat seal design. They are compatible with heat sealer machines for extra protection. Size: 7 x 10 cm Material: Aluminum foil Color: Black Package Contents: 100 x Flat food bags Note: Light and display differences may cause the color of the item to appear slightly different from the real thing. Measurement allows an error of +/- 1-3 cm.