"This is hopefully the worst filter on the market - the prospect of one
being worse is frightening. I tried it on several trips, and found it
always clogs up within seconds and is very hard to handle. The
filter has a ceramic ball that goes into the water, and can easily
attract sand. The pump piston seems to refuse to suck - I was able
to get it working in the sink at home by putting salad oil on the
rubber seals of the piston, but the pump was dry and not sucking
by the time I got it out in the field. Fortunately, others had working
pumps - mostly PUR products. Last weekend I watched a new
Boy Scout - out on his first backpack outing take his Basic
Designs filter to the creek and experience only frustration, with
problems just like I had. I told him to put it away, take it home,
return it, and buy a PUR ! Hiker for exactly the same price."