BlenderBottle Classic Shaker Bottle, 28-ounce, Black (2-Pack) Effortlessly mix protein drinks, pancake batter, sauces, dressings and more by shaking bottle with patented Blender Ball 28 ounce capacity to the rim of the cup with measurements on the back up to 20 ounces Stay-open flip cap, Gripper Bars make it easy to hold Cup made of BPA-free plastic; Blender Ball made of surgical grade stainless steel Dishwasher safe; do not use in microwave or with hot or warm liquids