The Hydro Flask is a water bottle that has a built-in filter that helps to remove any bacteria or other contaminants. To clean the filter, first unscrew the top of the Hydro Flask and place it in a sink with cold water. Pour enough water to cover the bottom of the filter and use a plunger to suction onto the top of the filter and pull. The water will flow through the filter and out of the Hydro Flask.
