Providing lightweight convenience for hikers, paddlers, bicyclists or backpackers, the 28 oz. capacity Katadyn Exstream XR Purifier Bottle is a fill-and-go water bottle that purifies water as you drink from it. Katadyn's Exstream purifiers are the only EPA-registered purification bottles that remove all types of organisms, including cysts, bacteria and viruses. The Exstream XR Purifier Bottle combines a purifier and water bottle into a single unit, eliminating the need for hoses or separate containers. No pumping is required and there's no need to allow time for purification to occur. The bottle houses a three-step purification system. A carbon pre-filter removes particulates and reduces unpleasant tastes and odors, ensuring fresh-tasting water. A cyst filter eliminates cysts, including Giardia and Cryptosporidium. Finally, water passes through a ViruStat microbial water purification cartridge which kills all waterborne bacteria and viruses. The entire process takes place in the brief moment required to squeeze the Exstream XR Purifier Bottle and drink from the hands-free, leak-proof bite valve. The bottle capacity of the Exstream XR Purifier Bottle is 34 oz. which, accounting for cartridge displacement, carries up to 28 oz. of drinkable water. The bottle fits conveniently in standard water bottle holders and an integrated carry loop allows for easy attachment to backpacks or kayaks. The replaceable cartridge produces up to 26 gallons, roughly 120 refills, of drinking water, depending on the quality of the water source. The Exstream XR Purifier Bottle is available in cobalt blue or olive color options. PLEASE NOTE: Katadyn items CANNOT be shipped outside of the USA.