Nothing is safer or easier to use for purifying the most demanding backcountry water sources than the MSR Guardian Purifier Pump. Originally designed for military squads, it brings this highly advanced technology to global travelers, backcountry users, and those stocking emergency kits. Fast and easy to use, this water purification pump offers the added viral protection you need when traveling in developing nations and popular wilderness areas. Its advanced hollow fiber filter offers the most reliable way to purify even filthy water conditions. Add its long-lasting performance and revolutionary self-cleaning ease, and this may be the only treatment device you&';ll ever need. Ultimate Protection: Meets NSF protocol P248, testing standard used by U.S. military, for removal of viruses, bacteria, protozoa, and sediment from "worst-case" water conditions. Fast & Easy: Pumps a rapid 2.5 liters per minute, offering added viral protection without the need for chemicals, bulbs, batteries, or waiting. Self-Cleaning: Pump self-cleans on every stroke, providing consistently fast flow rates with zero hassle-no backflushing or filter-scrubbing ever required. Long-Lasting: Leading-edge hollow fiber cartridge treats up to 10,000+ liters. Extremely Durable: Engineered to withstand heavy use, freezing, drops*, and harsh environments. SKU 02370 Weight (Standard) 1 Ibs 1 oz Weight (Metric) 0.49kg Width (Standard) 3 in Length (Standard) 8.25 in Height (Standard) 4.5in Effective Against Bacteria Yes Effective Against Chemicals/Toxins Yes Effective Against Particulate Yes Effective Against Protozoa Yes Effective Against Viruses Yes Filter Media Advanced Hollow Fiber Filter Pore Size (Microns) 0.02 Flow (L/min) 2.5 liters per minute Cartridge Life 10,000+ liters Field Cleanable Self-Cleaning Field Maintainable Yes Water Bottle Adapter Yes Cartridge Replacement Indicator Yes Materials Hollow Fiber Country of Origin Made in the USA