The Insulated Classic 32oz is based on our classic stainless steel water bottle combined with Climate Lock double-wall vacuum insulation, keeping drinks hot for 24 hours and iced for 90 hours! Klean Coat powder coat finish is 4X more durable, chip-resistant and safe for people and planet. 18/8 Stainless Steel construction. Climate Lock double-wall vacuum insulation will keep drinks hot for 24 hours and iced for 90 hours. Klean Coat powder coat finish is 4X more durable than our previous finish and formulated for human and environmental health (Brushed Stainless has no coating). Electropolished interior, a safe & non-toxic process, and rounded corners make it easy to clean. Hand washing is recommended for all Insulated products. Backed by the lifetime Strong as Steel guarantee.