The designers at Aquamira have come up with the ultimate pump free filter system. Small, compact, easy to use filter that prevents cross contamination. Connect to almost anything, using the universal connectivity system. The Frontier Pro filter will connect directly to any water bottle with a 28mm opening. Using the tube connection feature you can connect to the drink tube of your hydration system, or drink from any open container or water source. Since you drink directly from the unit there is no chance of confusing inlet and outlet tubes resulting in possible cross contamination. The Frontier Pro can also be set up in a “gravity flow” mode to filter water unattended while you pursue more enjoyable uses of your valuable outdoor time. BPA Free. Filter measures 7"L x 1" Dia. Weighs .20 lbs.