Abstract: A universal filter system is provided for filtering a fluid in a fluid container, such as water in a water bottle. The system can be selectively attached to and removed from a plurality of fluid containers. For instance, the filter system can be applied to a first fluid container. After use, the filter system can be removed from the first fluid container. The filter system can then be used in connection with the first fluid container again or with a different fluid container. The filter system can include a filter and one or more container-engaging elements that are configured to sealingly engage a portion of a plurality of fluid containers, including interior and/or exterior portions of such fluid containers. In this way, the leakage of a fluid from the container can be prevented and the fluid must pass through the filter before exiting the outlet of the fluid container.

Abstract: A universal filter system is provided for filtering a fluid in a fluid container, such as water in a water bottle. The system can be selectively attached to and removed from a plurality of fluid containers. For instance, the filter system can be applied to a first fluid container. After use, the filter system can be removed from the first fluid container. The filter system can then be used in connection with the first fluid container again or with a different fluid container. The filter system can include a filter and one or more container-engaging elements that are configured to sealingly engage a portion of a plurality of fluid containers, including interior and/or exterior portions of such fluid containers. In this way, the leakage of a fluid from the container can be prevented and the fluid must pass through the filter before exiting the outlet of the fluid container.