The tumbler is made of 304 food-grade 18/8 stainless steel, durable and shatterproof. Highly resistant to rust and to absorbing odor, taste. All components are non-toxic, BPA free and environmentally friendly, won't alter flavors. Safer and healthier than plastic or wine glasses.The wine tumblers are triple-insulated keep hot up to 3 hours and cold up to 9 hours.
