Keep Drinks even Colder/Hotter: Even the regular lids will keep drinks cold or hot for MANY hours. However the slide lock enclosure will add even more time to that.
Greatly Reduce Spills: While the slider lid isn't 100% spill-proof, it will greatly reduce the amount spilled while closed.
Premium Sipping Experience: The curvature of the slider lid provides a premium sipping experience.
*The 20oz Slider lid will work for 15oz Coffee Mugs as well.