The Shake It Large Capacity 28oz Shaker Cup Uses A Ball That Helps Combine Protein Or Other Drink Powder With Liquid & 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 & Ml Measurements, A Wide-Mouth Opening For Easy Cleaning, Integrated Carry Handle & a Flip Cap That Stays Out Of The Way When You Are Drinking. BPA-Free & Fits Most Car Drink Holders.