The 21 oz Ultralight Titanium Trail Series™ bottle is 35% lighter than our other 21 oz bottles thanks to a premium titanium design. Engineered to deliver the same cold refreshment you expect but without the weight, the Trail Series™ makes it easy to take your cold hydration as far as your spirit of adventure takes you. 35% lighter than our other 21 oz bottles means this ultralight titanium bottle weighs less so you can do more. Our first ever titanium construction makes this the lightest vacuum insulated bottle on the market. Titanium standard mouth cap with flexible perforated strap and titanium pivots cut weight in our leakproof design.