MSR Trail Base 2L Water Filter KitTo meet the needs of multi activity backcountry adventurers, we set out to engineer the most versatile water filter ever. The Trail Base microfilter kit features modular components that allow it to be used as a gravity system at camp, a pocket sized filter on the trail, or a fast and light reservoir when you need to carry clean water with you. Whether youre hiking, biking or basecamping, the Trail Base water filter kit offers incredible flexibility