Heat and reheat foods with the convenience of a built-in steam vent using this set of Performance 34-oz. Vented Glass Food Storage Containers. Featuring a unique 4-hinge locking system for freshness that lasts longer, LocknLock Purely Better storage containers are constructed from borosilicate glass, which can withstand both high heat and sudden cooling but is 10 percent lighter than tempered glass for easy, on-the-go use. The airtight and leakproof lid has been durability tested to last up to 3 million uses and features an innovative steam vent to prevent pressure build-up when foods are heating or reheating in the microwave. Plus, LocknLock Purely Better glass containers are microwave, freezer, oven, and dishwasher safe (lid not intended for traditional oven use). LocknLock Purely Better containers are also stain and odor resistant, easy to clean, and come with a Lifetime Limited Warranty for healthy, happy, no-worries food storage. Color: Clear.