J-I, I've been making this same packet of AquaPouch, coffee filters , filter holder, and water purification tablets for many years. However, I add a Seychelles Abvanced Water Straw as my final step to obtain pure water. My area of activity is very urban , so the straw gives me some protection against chemical contaminants in water I'm processing. How much protection, I cannot say for sure. But its compact, light and inexpensive. I can take it in places where a big filter unit might generate unwanted questions/ attention.