If you intend to travel where there are unreliable water sources then you need a water filter or purifier. Filters and purifiers protect against lots of parasites and water borne diseases, particularly Gardia. A ceramic filter will remove anything (bugs & dirt) in the water down to 0.2 microns while a purifier kills the bugs in the water but removes nothing. MSR filters screw onto the Nalgene bottle range to make for trouble free filtration.
£60.25 Saving 10%
Purifying water since 1999 complete with pre filter, 162g.
Prevent silt getting into your main filter with this handy add on, 26g.