Official Replacement Ultra Filter for the Survivor Filter PRO and Electric PRO X.Unlike our Competitors, Survivor Filter Backs up all its filtration claims with reputable North American Testing - Independent tests have shown that the 0.01 Micron Ultra Filter can filter out 99.999% of Virus and StaphCan be easily cleaned after every trip up to 100,000 Liters (26, 417 Gallons) for re-usable enjoymentOuter Shell Made of Military Grade BPA Free ABS materialTo replace, simply remove used Ultra Filter and replace with newThe internal Ultra Filter attaches to the Carbon Filter using a push and twist method to keep it securedThe Ultra Filter also features an O ring where it connects to the main water filter, which helps keep the device watertight.Beware of imitations and use only Official Survivor Filter replacement parts. All Survivor Filter products are shipped from North America.