Aquamira Series IV connectivity allows you to customize any Series IV system, such as the Frontier MAX or the Shift Bottles. The ultralight cartridge dramatically extends your filtration capabilities with less than 1oz of added pack weight. With 4 levels of filtration options there is a filter for every adventure.Features :Backcountry Plus FilterCompatibility with Frontier MAX or Shift Bottles1000 Gallon RatingRemoves 99% of Viruses, Bacteria and Cyst