[at-l] Water terminology

[Phil.Heffington@oc.edu (Phil Heffington)]

Term = Pre-filter

I have used the coffee filter method for a pre-filter but don't find it
as useful as the small plastic pre-filter with the small internal
element that I bought for a few bucks at the outfitters.  I doesn't do
much except filter out the trash and dirt, but that is enough to make my
PUR Hiker last much longer on the trail.

Also, it is good to know the difference in a "spring" and a "piped
spring".