Stainless Steel Construction: Spill-proof shaker bottle made of BPA-free stainless steel for mixing supplements and smoothies. Large 24-Ounce Capacity: Interior markings go to 20 ounces for plenty of room to mix supplements, meal replacements or water. Includes Wire Whisk: Features a 316 surgical-grade stainless steel wire whisk that mixes when the bottle is shaken for smooth shakes in seconds. Double-Wall Vacuum Insulation: Keeps drinks cold for up to 24 hours with a flexible, ergonomic carry loop for comfortable grip. Made from BPA and Phthalate-Free Materials: Hand wash cup and dishwasher-safe lid; not for use with hot liquids.