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MSR® 4L Trail Base™ Water Filter Kit Provides Two Filter Modes in One

New 4L system offers both gravity and trail filtration for ultimate versatility

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SEATTLE, Wash. (August 7, 2018) — Seattle-based Mountain Safety Research® (MSR®), the high-performance outdoor equipment brand, introduces the 4L Trail Base™ Water Filter Kit for 2019, expanding the capacity of its previously-release 2L filter kit. Both water filter kit sizes deliver gravity filtration for camp, a pocket-sized filter for the trail, plus a water storage bag to provide incredible flexibility and options – adapting to the needs of the adventure at hand.

“The Trail Base gives me exactly what I need, whether I’m training for a multi-week expedition or camping with my family,” said Eric Larsen, polar explorer and MSR ambassador. “When adventures are your profession, having a kit that perfectly adapts to multiple scenarios is incredibly valuable and the Trail Base does exactly that.”

The Trail Base Water Filter Kit is MSR’s most versatile filter ever created. Whether you’re heading out on a leisurely backpacking trip or embarking on a fast-paced adventure like trail running or mountain biking, the Trail Base Water Filter Kit provides the use mode you need to make your trip successful.

The kit’s hollow fiber filter meets the highest standards for removal of waterborne bacteria and protozoa at a flow rate of 1 liter per minute and cartridge life of 1,500 liters, and can be easily cleaned in the field, no tools required. Like all MSR water filters and purifiers, the Trail Base Water Filter Kit has a clear end of life indicator.

Designed for High-Achieving, Multi-Sport Adventurers

To meet the needs of multi-activity backcountry adventurers, the 4L Trail Base™ Water Filter Kit simply and seamlessly transitions from a small trail filter on fast-and-light adventures to a high-volume gravity filter for basecamp filtration. The included lightweight water storage bag ensures that clean water is always ready on demand for any activity, with a 3-in-1 cap for easy drinking and pouring.

MSR’s hollow fiber technology quickly and reliably removes harmful protozoa, bacteria, and particulate, including microplastics. Behind every MSR water treatment and hydration product is a team of scientists dedicated to researching, developing, and testing the latest in water treatment solutions. MSRP $149.95

  • Versatile: Modular components allow the system to quickly and easily transform from a 4L gravity system into a small trail filter and back.
  • Effective Against: Bacteria (99.9999%), protozoa (99.9%), and particulate including microplastics. Hollow fiber meets US EPA drinking water standards and NSF protocol P231 testing standard.
  • Simple Transitions: Trail filter simply quick-connects into gravity system to create the complete gravity-fed filter system.
  • Complete Kit: Includes ultralight, durable clean water reservoir featuring 3-in-1 cap for easy filling, drinking, and pouring
  • Flow Rate: 1 liter per minute
  • Weight: 516g (18.2oz)
  • Cartridge Life: 1500 L
  • Dimensions: 30.5 x 12.7 cm (12 x 5 in)

About MSR® (Mountain Safety Research®)

Seattle-based MSR has been engineering standard-setting high-performance outdoor equipment since 1969. A commitment to quality manufacturing and innovation ensures customers are outfitted with the finest, most reliable gear available for outdoor adventures. MSR product lines include: stoves, fuel, cookware, water treatment and hydration systems, shelters, snowshoes, snow tools, and backcountry poles. The majority of MSR products are made in the company’s Seattle, U.S.A. and Cork, Ireland manufacturing facilities. For more information, visit