30 Ounce Tumbler. The 30 ounce RAMBLER Tumbler by Yeti is an ample drinks carrier keeping things warm, cold or however you like them for longer. Kitchen-grade stainless steel is rugged, resisting rust and punctures. The double-wall vacuum insulation makes sure hot drinks stay hot and cold drinks stay cold. A magnetic closure on the lid locks down your bevvy. 18/8 stainless steel Rust, puncture-resistant Double wall vacuum insulated Shatter-resistant construction Dishwasher-safe MagSlider lid Mag