Advanced Replacement Water Filter Fits our 28oz Flip Top & 24oz Pull Top Bottles, the Pure Water Pump and 38oz Canteen. Reduces up to 99.99% of bacteria and chemicals Advance filter produces up to 100 gallons Can be used in extreme conditions; turbid and stagnant water; and is ideal for emergencies such as hurricanes, cyclones, etc. Not to be used with Salt Water.