Byron is vacuum insulated and keeps beverages hot for up to 6 hours and cold for up to 12 hours. The Snapseal technology makes the Byron leak proof and has a recess in the mouthpiece to allow sipping of hot beverages. Drink easily with one hand. To open, push the cap up, and to close, push the cap down again. The Soft Grip completes the drinking experience.Snapseal technologyThe Snapseal technology is unique Push the button up to drink, push the button down to lock the cup.