PACKAGE INCLUDE: you will get 300 pieces resealable mylar bags with 3 sizes in one package,and each size with 100 pieces.3 sizes are 3 x 4.7 inch,4 x 6 Inch,4.7 x 7.9 inch,the inner size reduce 0.4-1.2 inch. STRONG RESEALABLE ZIPPER: the resealable bags is designed with super strong zipper. You can either manual seal zipper part, or you can heat seal the open top section above the zipper, so that achieve storage effect, and these food storage bags can be applied many times. CONVENIENT TO USE: just open and seal zipper part, very easy to use for packing and storing, clear frosted front window design allowing for a quick glance at contents inside, please make sure to close the zipper seal tight to prevent leakage and ensure freshness PREMIUM QUALITY MATERIAL: these sample bags is made of polyethylene , aluminum foil and mylar, composed of three layers of materials.durable, non-toxic and tasteless. WIDE APPLICATIONS: these packaging bags is perfect for store food ,like coffee beans, cookie, tea, nuts, dried fruit, snacks.And store more items, like lip gloss ,eyelash ,sample ,jewelry ,electronics,craft,etc