Specifications Size:25L Material: TPU coated Nylon, Night reflecting strap and handle Flow rate: up to 1L/min Life capacity: 3000L Feature: √Ultra-portability √Adapt to the soft drinking bottle neck √Gravity filter; 0.1 micron (0.0001 mm) with Hollow fiber UF √Instant filtration, Effective filtration anytime & anywhere √Removes 99.9999% bacteria √Removes 99.9% protozoa √Removes Bacteria, protozoa, E. Coli, giardia, vibrio cholera, Salmonella tophi etc √Up to 1000ml/min with bag pressure √Up to 3500L depending on water quality √Quick connection with auto-close value Package Content: 1 x 25L Backpack&Water Filter 1 x Attached Shower Head 1 x User Guide Frequently A&Q 1. Lifetime of the filter cartridge? Filter cartridge capacity is approximately 3500 liters (the equivalent of 7,000 bottles of mineral water), depending on usage and the environment. It lasts for couple years for the general outdoor activities. 2. What is flow rate of filter？ Initial flowrate up to 1000 ml per minute, depending on the height above sea level and water conditions, around 45L filtered water at sea level. 3. What is affecting factor of flowrate? Waterproof backpack & Filter User’ Manual A flow rate of the filter is determined by a combination of: water pressure (the distance from the top of the water to the filter), the altitude, the cleanliness of the water, the cartridge itself (the subtle differences between each cartridge).