Stainless steel, spill-proof BlenderBottle, for mixing supplements and smoothies, features an easy-open/easy-close push-button flip cap with a sliding lock to prevent accidental opening | 24-ounce capacity (interior markings go to 20 ounces) offers plenty of room for supplements, meal replacements, or water | Includes a 316 surgical-grade stainless steel BlenderBall 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; flexible, ergonomic carry loop provides a comfortable hold | Made from high-quality BPA and phthalate-free materials; hand wash cup, dishwasher-safe lid; not for use with hot liquids