LOCK & LOCK GLASS, 1.6 Cup, Borosilicate Glass, Oven Safe, BPA Free, 100% Airtight, Glass Round Food Storage Container with Lid Excellent airtight and watertight with patented 4-hinge locking system with silicone sealing ring Heat resistant up to 750 & Thermal shock resistant up to 248 Safe Material for storage & cooking without risk of spontaneous breakage & shattering Microwave, Oven(without lid), Freezer, and Dishwasher safe Product of the year, 2010(UK) / Red Dot Design Award Winner, 2011(Germany)