The perfect blend of strength and style. This tumbler/shaker combo gives you the best of both worlds-sip or swig dual lid, effortless mixing, 24-hours cold insulation, and more. Once you try it, no road trip, workout class, or lifting session will be the same without it.? Features: Keeps beverages cold up to 24 hours Leak-proof with straw removed Rounded base for better mixing Dual-function lid for straw or straw-free sipping Double-wall insulated stainless steel Measurement markings BPA and phthalate-free Powerful mixing system