Hate clumps and chunks in your protein shakes? So does Progenex. Which is why they've searched for the best shaker bottle ON THE PLANET. Here it is. Mix a perfect no-clump shake thanks to the wire ball that helps mix the thickest ingredients effortlessly. Enjoy a smooth, perfect shake—every time! Made of BPA-free plastic. 28 oz. max capacity. Ideal for 8-20 oz. drinks.