Durable - 3-MIL thick metallic mylar provide durability and protects inner contents from UV and water vapor damage. Pack, transport and story without worry. Heat Sealable - Prolong the shelf-life of your product by heat sealing after filling. We recommend impulse heat sealers. Outer Size: 12x18cm (4.7x7.1") Inner Size: 10.5x17.5cm (4.1x6.9"), *Size may vary 2-3mm. Perfect for sampling products! Mylar foil bags are one of the most popular packaging options in all industries. Our packaging bags come in a variety of colors and designs to capture the style of your product. The small size is perfect to create sample packs of your products.