Anchor Hocking TrueSeal 10-Piece Glass Storage Set : The TrueSeal lid technology of this stackable Anchor Hocking 10-piece glass storage set features compression lids for airtight freshness and spillproof storage. Provides audible and visual proof of the food-preserving vacuum: press the clear center of the lid and hear the release of air - the lids stay recessed for a custom-fit seal. Thick-walled, tempered glass in a variety of sizes will heat food in the microwave, store food or sauces in the refrigerator. Preserve staples in a pantry and see exactly what is stored inside. Transparent windows for easy viewing. This durable set nests without the lids or stack for compact storage. Anchor Hocking tempered glass bowl set with TrueSeal lids was the only product, from 28 tested by the Good Housekeeping Research Institute, that earned a perfect score for airtightness. Microwave-safe. Lids are BPA-free. Glass bowls are oven-safe up to 425 F in gas and electric ovens. Freezer- and top-rack dishwasher-safe. 5-year limited manufacturer warranty. Product Features TrueSeal lid technology of Anchor Hocking 10-piece set features center lid compression for airtight freshness and spillproof storage Thick-walled glass to heat food in the microwave, store food in the refrigerator and preserve staples in the pantry Audible and visual proof of the food-preserving vacuum: pressing the center releases air - lids stay recessed Clear glass and transparent windows to view contents This 10-piece glass bowl set with TrueSeal lids was the only product, from 28 tested by the Good Housekeeping Research Institute, that earned a perfect score for airtightness Anchor Hocking is the premier manufacturer of cooking dishes and bakeware since 1905 Set includes: One - 1-cup with lid Two - 2-cup with lids (two) One - 4-cup with lid One - 7-cup with lid