20 oz Stainless Steel Tumbler with Bamboo Lid & Straw. Stainless Steel Outer & Inner walls. Double-wall vacuum insulated. Keeps your drinks hot or cold for hours (can keep cold more than 8 hours and keep hot more than 8 hours). Bamboo lid w/ rubber gasket & straw. BPA-Free. Sweat-resistant. Ships assembled. Hand wash recommended.