Era Flip 30oz is the world’s first 100% leakproof, covered, flip-down, straw tumbler. It has Brumate's fully leakproof SlideSeal™ lid that works for both cold and iced carbonated beverages, SoftSip™ silicone straw so every sip feels like a luxury, ColdKey™ metal straw for minimizing the amount of plastic sitting in your water, BevGuard™ technology to keep your drinks cold for 24+ hours, and a cup holder friendly base so you can enjoy your favorite beverages, free of leaks and spills throughout your daily journey. Made for stress-free sips. Era Flip Tumblers are 100% leakproof with cold beverages and carbonated beverages with ice when in the locked position. Not recommended to be used in the locked position with hot beverages.  Not recommended for use with hot beverages. Use at least 25% ice with carbonated beverages Warning:  Choking Hazard - small parts not for children under 6 years or any individuals who have a tendency to place inedible objects in their mouths. Silicone Tip is removable and may come off if bitten or pulled. Make sure it's securely in place during use.