These Dry-Packs Moisture Barrier Bags with Static Shielding are made from multiple layers of metalized polyester and dissipative polyethylene, making them durable and secure for whatever items you might be shipping or storing. The flexible structure makes it is easy to vacuum seal and is resealable with a built in zipper, effectively sealing out moisture or any other damaging factors. Whether you're shipping or storing metal items, electronic equipment, food, handguns, pharmaceuticals, or other sensitive items, these bags are perfect for keeping items in an airtight environment. With a low oxygen and moisture transmission rate, high light resistance, and high puncture resistance, these bags are perfect for keeping small items completely unaffected by any issues that may occur during shipment. Our Moisture Barrier and Static Shielding recloseable bags are the superior moisture resistant bags in the industry, and a perfect anti-corrosion storage solution for metal items. Bag walls are 5mil thick. Outer dimensions are 12.00" x 9.00". Inner dimensions are 10.00" x 8.25". Space between zipper and top is 1.50" to allow heat sealing if desired.