With the Nalgene Tritan On the Fly 24 oz. Water Bottle's convenient, one-handed cap design, you don't have to drop everything to take a sip. Its slim shape and leak-proof cap make it ideal for workbags, gym bags, and backpacks alike - without worry that it's going to give your stuff a soak. One handed operation with push button. Fits in most cup holders and bike cages. Made from durable Tritan plastic. BPA, BPS and Phthalate free.