Get unbeatable protection with new Power Shield technology featuring an easy close slider, new more durable film and expandable bottomStronger* than Hefty on punctures & tears *Bag film tested using ASTM D1709 Dart Drop and ASTM D2582 PPTPack includes 20 Ziploc brand Storage Slider Bags made of durable and long-lasting BPA-free plastic* *Product not formulated with BPA (Bisphenol A)Filled bags stand side by side in most refrigerators, freezers and pantriesSafe for use in microwaves (use as directed). When defrosting and reheating food, open the storage bag zipper one inch to vent