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; plenty of room for supplements, meal replacements, or water. Includes Wire Whisk: 316 surgical-grade stainless steel BlenderBall whisk mixes when bottle is shaken for smooth shakes in seconds. Double-Wall Vacuum Insulation: Keeps drinks cold for up to 24 hours; flexible carry loop provides comfortable grip. Made from BPA and Phthalate-Free Materials: Hand wash cup, dishwasher-safe lid; not for use with hot liquids.