The RapidPure 2.5" Replacement Purifier Cartridge lets you keep using your RapidPure Pioneer Scout or Intrepid for years to come. This water filter replacement element is easy to install and reduces your environmental impact by letting you reuse the same water purification system again and again. More than a filter RapidPure purifies water by removing over 99.99% of viruses bacteria parasites sediment and more. With no priming pumping or batteries required this fast water filter is also the best water purifier for personal use and works even after it has been frozen.