Prefilter Water Bottle Attachment

The 40x40 micron screen Pre Filter fits perfectly on wide mouth one liter water bottles and removes particulates that can get in the way of UV light in water. The Pre Filter is designed to be stored directly on a wide mouth bottle and the SteriPEN Classic 3 or SteriPEN Ultra fit perfectly in the filter. Just insert SteriPEN in the filter opening, turn the bottle upside down, and gently rock to circulate light throughout bottle.