550 Ml Shaker Cup with Supplements Storage & Wire Ball For Best Shaking Experience makes it easy to maintain proper nutrition and hydration on-the-go. Featuring a patented mixing system with a 316 surgical-grade stainless steel Blender Ball wire whisk (found only in Blender Bottle brand shaker cups) that moves freely inside the bottle to smooth out drink mixes and meal ingredients its ideal for protein shakes smoothies fiber drinks and meal replacements. Its also a handy kitchen tool for mixing pancake batter scrambled eggs and salad dressings. The wide mouth makes it easy to add scoops of powdered mixes meal ingredients and liquids and embossed markings show milliliters for easy measuring anywhere. Bottle contents and liquids are securely contained thanks to a tightly threaded screw-on lid that creates a leakproof seal and a flip cap that snaps securely shut for shaking and transportation. The convenient loop top makes it easy to carry the bottle and offers a place to attach car keys while at the gym. The Shaker Bottle can also be used as a water bottle; the ball can be left inside as it will never rust chip or peel. BPA and phthalate-free dishwasher safe.