In 2004, the Blender Bottle Classic revolutionized the market with its leak-proof lid, unique design, and Blender Ball for perfect mixing. Today, years later, it remains the best-selling shaker on the market. Why? Because it works. No more lumpy protein shakes. From now on, your drinks will always be perfectly blended and irresistibly delicious. The Blender Ball mixes with the right power, making the mixing grids in other shakers look outdated. Just add your ingredients, toss in the Blender Ball, and shake. The Blender Ball whirls through the bottle, giving your shake a smooth and airy consistency. The revolutionary loop allows you to conveniently carry your Classic Loop on a finger or attach it with a carabiner to your gym bag, backpack, or belt. The special feature of these shakers is that they are leak-proof. The unique lid is secure when you hear the click sound.