The Klean Kanteen Loop Cap was designed with athletes and multi-taskers in mind. The handy attachment loop makes it easy to clip your Klean Kanteen? onto your backpack, climbing harness, messenger bag or any other place you need quick, easy access to your drink.Made from polypropylene (pp#5). No BPA, phthalates, lead or other toxins. Handy attachment loop. Interchangeable with all Klean Kanteen Classic sizes. Dishwasher safe. Wt. 1 oz. Size: 2.75"H x 2"W.