If you work up a big thirst, the 22 oz is for you.
The silicone flip top seals when plugged but is not upside-down, bottom-of-the-bag leakproof.
The Flip Cap provides a narrow-mouth spout for on-the-go drinking. The medical-grade silicone flip top seals with the polypropylene (PP#5) cap.
The pivoting handle provides a great way to carry the bottle and stows out of the way while drinking.