Give your dog water wherever you go with H2O4K9, the lid is the bowl. H2O4K9 Bottles are made from #304 stainless steel which is 100-percent recyclable, so after the many years (perhaps decades) of use you'll get from your H2O4K9 bottle you can take comfort in knowing your bottle can be recycled and used for other applications. H2O4K9 Lids are made from Polypropylene #5 which is also recyclable and will not release BPA or phthalates. H2O4K9 Bottles fit standard cup holders, backpacks, bike bottle holders, as well as the NEOSLING. Using H2O4K9 Bottles eliminates the need to carry and dispose of plastic water bottles. Although these plastic bottles are easily recyclable, about 90-percent of the pet water bottles sold each year wind up in landfills. Safe materials; with no hinges or complex parts that can break or rust.