The Shake It large capacity 28 oz. shaker cup uses a ball that helps combine protein or other drink powder with liquid and break up lumps to give you a smooth drink. Be sure to add the liquid before you add the powder to prevent it from clumping on the sides or bottom. Features include ounce and ml measurements, a wide-mouth opening for easy cleaning, integrated carry handle and a flip cap that stays out of the way when you are drinking. BPA-free and fits most car drink holders.