40oz Era Leakproof Tumbler, Assorted40oz Era Leakproof Tumbler Big Sips. Zero Stress. A new era of straw tumblers is officially here, and shes built for hydration without the hassle. The Era Tumbler 40oz delivers totally leakproof confidence with luxe sipping comfort, so you can carry more, sip easier, and spill less through every part of your day. Why you'll love it Fully leakproof Turn lid for stress free sipping on the go Works with cold and carbonated beverages when locked ColdKey