Keep your drinks warm or cool for up to 6 hours while traveling on a business trip or at the office. The Sierra Tumbler is simply designed to help prevent those annoying spills and help keep drinks at a consistent temperature for a longer time. Specs: Outer and inner Stainless steel double wall construction for insulation, Snap-on spill-resistant thumb-slide lid with rubber gasket, Capacity is 18 oz. with the lid on, Non-slip bottom BPA free, meets FDA requirements, wash by hand recommended