Astonishing Sealing - 4 Side Locking That Locks Twice Presents The Most Astonishing Sealing Compared To Other Brand Products. Excellent Durability And Safe Materials - ‘Hinge’ And Patent Technology Of ‘Blocking Hole’ Of Locknlock Gives You Excellent Durability That Guarantees More Than 3 Million Times Of Opening And Closing. Safe Polypropylene (Pp) Allows You To Use It In The Microwave And Dishwasher. Excellent Space Use - It Is Scientifically Designed For Easy Stacking Both Upward And Side Direction From The Product Development Process. This Product Shows An Excellent Space Use. Quality Acknowledged - 12 Fields Including Safety, Sealing, Durability, Lid’S Open/Close Function, Microwave Usage And Cleaning Manageability.