I bought this specifically to fit in the cup-holders of my treadmill - which it does perfectly. Since I read other reviews, I know to push down the white button to prevent the whistling sound when drinking. If I'm not careful about really pushing down on the cap, it leaks a little.
Purchased 18 oz. bottle in 'stainless' finish to add to our collection of 27 oz. bottles, which are just a bit too large to carry around sometimes. New sport top is great and much easier (and neater) to drink from than previous screw-on top. These are Kleen Kanteen products -- well-made, great in dishwasher and very durable. Engraving is a nice option also.
