6KU Little Big Mouth Bottle by Specialized. 21 oz capacity.  Purist technology shields the inside of the bottle from any bad taste, mold, or staining. Nothing sticks, so your bottle stays clean and your water tastes pure. This technology naturally shields the inside of your bottle. Exactly the same way a lotus leaf shields itself to maintain its purity. Technology truly inspired by nature. Simple water bottle cage for most bikes with a pre-drilled boss. * Constructed using a 6mm aluminum rod * Embossed MSW logo