Pyrex glass storage set 1)Air-tight and microwavable 2)Keep food fresher longer than plastic one 3) ... glass bakeware,glass casserole, glass lid, glass bowl, glass storage set, glass container, glass ovenware, glass plate,glass dish, microwave glassware ... )No environmental risk. That is interesting for you: 1) Composition and corrosion resistance 2) Physical properties 3) Operating conditions of glass ...