The Klean Kanteen Sport 3.0 cap is a sports screw cap for bottles with a neck diameter of 4.4 cm. The whole is made of polymer, but the lever is made of silicone. It has a membrane that ensures that no liquid leaks out spontaneously even after unlocking the drinker. You have to suck the water into your mouth. Then the membrane lets air into the bottle, releasing the liquid.
Like Klean Kanteen bottles, it is BPA-free and does not affect the taste of the stored beverage. The top of the cap is a polymer loop that attaches the bottle to your tactical gear. Simply pull the loop through the carabiner and the bottle stays nailed to your backpack or belt. The loop is even wide enough to comfortably slip a finger through and you can carry the bottle on shorter walks.