Simple Elegant Design spill proof coffee travel mug with screw-in cup lid is equipped with a airtight silicone sealing ring, which provides a good leak-proof. Flip lid opens and locks easily, You can open the flip lid with thumb in one second. Reliable Screw-On Leak proof Lid: It uses a screw-on lid design, which can click securely into the closed position. If the lid latched, you can turn the travel cup at any angle with confidence and don't need to worry about it will spill and cause leaks in your travel or office bag. Just bring your beverages to go!